CI: Move the documentation check to a separate job #2

	name: "CI - Documentation Check"

	on:
	push:
	paths:
	# NOTE: GitHub Actions do not allow using YAML references, the same path
	# list is used below for the pull request event. Keep both lists in sync!!

	# this file as well
	- .github/workflows/ci-yardoc.yml
	# all Ruby files
	- service/Gemfile*
	- service/*.gemspec
	- service/**.rb
	# the D-Bus introspection files
	- doc/dbus/**.xml

	pull_request:
	paths:
	# NOTE: GitHub Actions do not allow using YAML references, the same path
	# list is used above for the push event. Keep both lists in sync!!

	# this file as well
	- .github/workflows/ci-yardoc.yml
	# all Ruby files
	- service/Gemfile*
	- service/*.gemspec
	- service/**.rb
	# the D-Bus introspection files
	- doc/dbus/**.xml

	jobs:
	ruby_doc:
	runs-on: ubuntu-latest

	steps:

	- name: Git Checkout
	uses: actions/checkout@v3

	- name: Refresh repositories
	run: sudo apt-get update

	- name: Install Ruby development files and XML tooling
	run: sudo apt-get install -y --no-install-recommends ca-certificates gcc g++ libaugeas-dev libssl-dev make xmlstarlet

	# this only works in Ubuntu...
	- uses: ruby/setup-ruby@v1
	with:
	working-directory: ./service
	# the current TW version
	ruby-version: "3.2"
	# runs 'bundle install' and caches installed gems automatically
	bundler-cache: true

	- name: Generate doc
	working-directory: ./service
	run: bundle exec yardoc --fail-on-warning

	- name: Check that introspected API and its docs have not diverged
	working-directory: ./doc
	run: make check

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