Add CI/benchmarks for Ruby 3.3 #1088

	name: Main
	on:
	pull_request:
	branches:
	- main
	push:
	branches:
	- main
	jobs:
	ci:
	name: CI
	strategy:
	fail-fast: false
	matrix:
	# Due to https://github.com/actions/runner/issues/849, we have to use
	# quotes for '3.0' -- without quotes, CI sees '3' and runs the latest.
	ruby: [2.4, 2.5, 2.6, 2.7, '3.0', 3.1, 3.2, 3.3, jruby, truffleruby-head]
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	# Conditionally configure bundler via environment variables as advised
	# * https://github.com/ruby/setup-ruby#bundle-config
	- name: Set bundler environment variables
	run: \|
	echo "BUNDLE_WITH=checks:docs" >> $GITHUB_ENV
	if: matrix.ruby == 3.3

	# Use 'bundler-cache: true' instead of actions/cache as advised:
	# * https://github.com/actions/cache/blob/main/examples.md#ruby---bundler
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: ${{ matrix.ruby }}
	bundler-cache: true

	# - run: bundle exec rspec

	# - uses: codecov/codecov-action@v3
	# with:
	# files: ./coverage/coverage.xml
	# fail_ci_if_error: true # optional (default = false)
	# verbose: true # optional (default = false)
	# if: matrix.ruby == 3.3

	# - run: bundle exec rubocop
	# if: matrix.ruby == 3.3

	# - run: \|
	# bundle exec yard doctest
	# bundle exec dokaz
	# if: matrix.ruby == 3.3

	- name: Run benchmarks on Ruby 2.7 or 3.3
	run: \|
	BUNDLE_GEMFILE=benchmarks/Gemfile bundle install --jobs 4 --retry 3
	RUBY_YJIT_ENABLE=1 BUNDLE_GEMFILE=benchmarks/Gemfile bundle exec ruby benchmarks/benchmarks.rb
	if: matrix.ruby == '2.7' \|\| matrix.ruby == '3.3'

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