Remove documentation build template details

Removed documentation build template section from README.

Author: jeromekelleher

README.md

@@ -1,23 +1,3 @@
 # .github
 Defaults for github shared across tskit-dev repositories
 
-### Documentation Build Template
-
-**File:** `.github/workflows/docs-build-template.yml`
-
-A reusable workflow for building documentation across all TSKit ecosystem repositories. This eliminates duplication of nearly identical documentation workflows.
-
-**Usage:**
-```yaml
-jobs:
-  docs:
-    uses: tskit-dev/.github/.github/workflows/docs-build-template.yml@main
-    with:
-      requirements-path: requirements/CI-docs/requirements.txt  # optional
-      additional-setup: sudo apt-get install -y libgsl0-dev    # optional  
-      make-command: make -C python                             # optional
-```
-**Parameters:**
-- `requirements-path`: Path to documentation requirements file (default: `requirements/CI-docs/requirements.txt`)
-- `additional-setup`: Additional setup commands (system packages, special builds, etc.)
-- `make-command`: Make command for building C modules before docs