Remove broken links

Closes #24046.

PiperOrigin-RevId: 688705897
Change-Id: Iddece5ef559775eda356157ebabacc8699fc8424

site/en/install/index.md

@@ -18,15 +18,13 @@ You can find available Bazel releases on our [release page](/release).
 Bazel community members maintain these packages. The Bazel team doesn't
 officially support them. Contact the package maintainers for support.
 
+*   [Alpine Linux](https://pkgs.alpinelinux.org/packages?name=bazel*&branch=edge&repo=&arch=&origin=&flagged=&maintainer=){: .external}
 *   [Arch Linux][arch]{: .external}
-*   [CentOS 6](https://github.com/sub-mod/bazel-builds){: .external}
 *   [Debian](https://qa.debian.org/developer.php?email=team%2Bbazel%40tracker.debian.org){: .external}
 *   [FreeBSD](https://www.freshports.org/devel/bazel){: .external}
-*   [Gentoo](https://packages.gentoo.org/packages/dev-util/bazel){: .external}
 *   [Homebrew](https://formulae.brew.sh/formula/bazel){: .external}
 *   [Nixpkgs](https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/tools/build-managers/bazel){: .external}
 *   [openSUSE](/install/suse)
-*   [Parabola](https://www.parabola.nu/packages/?q=bazel){: .external}
 *   [Scoop](https://github.com/scoopinstaller/scoop-main/blob/master/bucket/bazel.json){: .external}
 *   [Raspberry Pi](https://github.com/koenvervloesem/bazel-on-arm/blob/master/README.md){: .external}