Drop installation chapter as it requires network during build

--- ci/generate-docs.py.orig	2023-03-20 19:43:40 UTC
+++ ci/generate-docs.py
@@ -351,17 +351,6 @@ TOC = [
         ],
     ),
     Page(
-        "Download",
-        "installation.md",
-        children=[
-            Page("Windows", "install/windows.md"),
-            Page("macOS", "install/macos.md"),
-            Page("Linux", "install/linux.md"),
-            Page("FreeBSD", "install/freebsd.md"),
-            Page("Build from source", "install/source.md"),
-        ],
-    ),
-    Page(
         "Configuration",
         "config/files.md",
         children=[
--- docs/contributing.md.orig	2023-03-20 19:43:40 UTC
+++ docs/contributing.md
@@ -8,7 +8,7 @@ If you're thinking of helping out, then the following 
 * [WezTerm on GitHub](https://github.com/wez/wezterm)
 * [GitHub Discussions](https://github.com/wez/wezterm/discussions)
 * [Realtime conversation with wez on Element.io/Gitter](help.md)
-* [Building from Source](install/source.md)
+* [Building from Source](https://github.com/wez/wezterm/blob/main/docs/install/source.markdown)
 * [Where to find things and hacking on wezterm](https://github.com/wez/wezterm/blob/master/CONTRIBUTING.md#contributing-to-wezterm)
 
 I like to think that I have an open mind and I try to be open to ideas,
--- docs/index.md.orig	2023-03-20 19:43:40 UTC
+++ docs/index.md
@@ -7,8 +7,6 @@ ---
 
 ![Screenshot](screenshots/wezterm-vday-screenshot.png)
 
-[Download :material-tray-arrow-down:](installation.md){ .md-button }
-
 ## Features
 
 * Runs on Linux, macOS, Windows 10 and FreeBSD