Update documentation to reflect OSes that don't run acceptance tests

[bschonec]

Gentoo is not supported by metadata/beaker.

SLES and RHEL do not run acceptance tests because they both require valid licenses in order to install required packages.

This behavior is not documented (at least not that I've found) and for someone unfamiliar with the Voxpupuli workflow, it's difficult to understand why SLES/RHEL don't run tests without a deep dive into the source code.

I recommend updating the README.md to explain this behavior to those unfamiliar. One advantage would be to make it easier for non-developers to contribute to Voxpupuli in general.

[ekohl]

Technically it's this bit that determines whether acceptance tests are supported:

puppet_metadata/lib/puppet_metadata/beaker.rb

Lines 85 to 89 in bb8ecac

	# Return whether a Beaker setfile can be generated for the given OS
	# @param [String] os The operating system
	def os_supported?(os)
	%w[Archlinux CentOS Fedora Debian Ubuntu Rocky AlmaLinux OracleLinux].include?(os)
	end

Edit: when linking to a line on GitHub you should get the absolute URL which includes the commit blob. You can press y to change the URL. This is because line numbers change over time.

Gentoo is not supported by metadata/beaker.

[ekohl]

I've opened a PR for a new blog post: voxpupuli/voxpupuli.github.io#328