Fix PR builds that are failing due to "broken links" (#2142)

## Changes

- Fixes the PR builds after a silent update to `lychee` 0.23.0.

## Context

Since February 28th, 2026, [our PR
builds](https://github.com/git/git-scm.com/actions/workflows/ci.yml) are
failing consistently (which I noticed only today):

<img width="1390" height="481" alt="image"
src="https://github.com/user-attachments/assets/7ef02719-0ef1-4983-b318-dd4c4240beab"
/>

The reason is not that all of a sudden, this project only receives
crappy contributions. The reason is that a silent upgrade of `lychee` to
0.23.0 (which did not require a separate upgrade of the `lychee` GitHub
Action, apparently) now makes the use of `--root-dir` mandatory when
referring to absolute paths in, say, the `.css` files.

The symptom looks like this:

> # Summary
> 
> | Status         | Count   |
> |----------------|---------|
> | 🔍 Total       | 1708256 |
> | ✅ Successful  | 1694831 |
> | ⏳ Timeouts    | 0       |
> | 🔀 Redirected  | 0       |
> | 👻 Excluded    | 13397   |
> | ❓ Unknown     | 0       |
> | 🚫 Errors      | 28      |
> | ⛔ Unsupported | 0       |
> 
> ## Errors per input
> 
> ### Errors in
public/application.min.71f7939ea93a5a92743051d3cd11096ae5cec3a3c519720942f820ce92c1d41b.css
> 
> * [ERROR] <error:> | Error building URL for "/images/bg/body.jpg"
(Attribute: Some("url")): Cannot convert path '/images/bg/body.jpg' to a
URI: To resolve root-relative links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for "/images/bg/body.jpg"
(Attribute: Some("url")): Cannot convert path '/images/bg/body.jpg' to a
URI: To resolve root-relative links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/bg/isometric-grid.png" (Attribute: Some("url")): Cannot convert
path '/images/bg/isometric-grid.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/bg/isometric-grid.png" (Attribute: Some("url")): Cannot convert
path '/images/bg/isometric-grid.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/bg/isometric-grid.png" (Attribute: Some("url")): Cannot convert
path '/images/bg/isometric-grid.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/bg/search-header.jpg" (Attribute: Some("url")): Cannot convert
path '/images/bg/search-header.jpg' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/admin-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/admin-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for "/images/icons/book.png"
(Attribute: Some("url")): Cannot convert path '/images/icons/book.png'
to a URI: To resolve root-relative links in local files, provide a root
dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/branch-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/branch-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/camera-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/camera-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/debugging-sm.png" (Attribute: Some("url")): Cannot
convert path '/images/icons/debugging-sm.png' to a URI: To resolve
root-relative links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/document.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/document.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/document.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/document.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/download.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/download.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/email-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/email-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/external-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/external-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for "/images/icons/info.png"
(Attribute: Some("url")): Cannot convert path '/images/icons/info.png'
to a URI: To resolve root-relative links in local files, provide a root
dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/inspection-sm.png" (Attribute: Some("url")): Cannot
convert path '/images/icons/inspection-sm.png' to a URI: To resolve
root-relative links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/patching-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/patching-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/plumbing-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/plumbing-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/projects-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/projects-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for "/images/icons/search.png"
(Attribute: Some("url")): Cannot convert path '/images/icons/search.png'
to a URI: To resolve root-relative links in local files, provide a root
dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/server-admin-sm.png" (Attribute: Some("url")): Cannot
convert path '/images/icons/server-admin-sm.png' to a URI: To resolve
root-relative links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/setup-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/setup-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/sharing-sm.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/sharing-sm.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/icons/sidebar.png" (Attribute: Some("url")): Cannot convert
path '/images/icons/sidebar.png' to a URI: To resolve root-relative
links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/logos/downloads/Git-Icon-1788C.png" (Attribute: Some("url")):
Cannot convert path '/images/logos/downloads/Git-Icon-1788C.png' to a
URI: To resolve root-relative links in local files, provide a root dir
> * [ERROR] <error:> | Error building URL for
"/images/sidebar-divider.png" (Attribute: Some("url")): Cannot convert
path '/images/sidebar-divider.png' to a URI: To resolve root-relative
links in local files, provide a root dir

Simply providing a `--root-dir` option fixes this.

Author: dscho

.github/workflows/ci.yml

@@ -84,6 +84,7 @@ jobs:
           --exclude file:///Pfad/zum/Repo.git/
           --exclude file:///chemin/du/d%C3%A9p%C3%B4t.git/
           --exclude file:///srv/git/project.git
+          --root-dir public/
           public/
         output: lychee.md
         jobSummary: true