Alpine, Arch Linux, Fedora, RHEL, NixOS Root on ZFS guide: add CI/CD tests

Remove unmaintained Arch Linux guides.

Signed-off-by: Maurice Zhou <yuchen@apvc.uk>

scripts/zfs_root_gen_bash.py

@@ -0,0 +1,13 @@
+#!/usr/bin/env python3
+#
+# Copyright 2023 Maurice Zhou <yuchen@apvc.uk>
+#
+# Released without warranty under the terms of the
+# Apache License 2.0.
+
+import pylit
+
+pylit.defaults.code_block_markers['shell'] = '::'
+pylit.defaults.text_extensions = [".rst"]
+
+pylit.main()