[Docs] Minor edits

Author: peterschmidt85

docs/docs/concepts/fleets.md

@@ -4,8 +4,8 @@ Fleets act both as pools of instances and as templates for how those instances a
 
 `dstack` supports two kinds of fleets: 
 
-* [Backend fleets](#backend) – dynamically provisioned through configured backends; they are supported with any type of backends: [VM-based](backends.md#vm-based) and [container-based](backends.md#container-based) (incl. [`kubernetes`](backends.md#kubernetes))
-* [SSH fleets](#ssh) – created using on-prem servers; do not require backends
+* [Backend fleets](#backend-fleets) – dynamically provisioned through configured backends; they are supported with any type of backends: [VM-based](backends.md#vm-based) and [container-based](backends.md#container-based) (incl. [`kubernetes`](backends.md#kubernetes))
+* [SSH fleets](#ssh-fleets) – created using on-prem servers; do not require backends
 
 When you run `dstack apply` to start a dev environment, task, or service, `dstack` will reuse idle instances from an existing fleet whenever available.
 

docs/docs/installation/index.md

@@ -1,8 +1,8 @@
 # Installation
 
-!!! info "dstack Sky"
+<!-- !!! info "dstack Sky"
     If you don't want to host the `dstack` server (or want to access GPU marketplace),
-    skip installation and proceed to [dstack Sky :material-arrow-top-right-thin:{ .external }](https://sky.dstack.ai){:target="_blank"}.
+    skip installation and proceed to [dstack Sky :material-arrow-top-right-thin:{ .external }](https://sky.dstack.ai){:target="_blank"}. -->
 
 ## Set up the server
 

docs/docs/quickstart.md

@@ -1,6 +1,6 @@
 # Quickstart
 
-> Before using `dstack`, ensure you've [installed](installation/index.md) the server, or signed up for [dstack Sky :material-arrow-top-right-thin:{ .external }](https://sky.dstack.ai){:target="_blank"}
+> Before using `dstack`, ensure you've [installed](installation/index.md) the server.
 
 ## Set up a directory