Relax webrick and rack version requirements #21

	# This workflow uses actions that are not certified by GitHub.
	# They are provided by a third-party and are governed by
	# separate terms of service, privacy policy, and support
	# documentation.
	# This workflow will download a prebuilt Ruby version, install dependencies and run tests with Rake
	# For more information see: https://github.com/marketplace/actions/setup-ruby-jruby-and-truffleruby

	name: Ruby

	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	jobs:
	test:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	ruby-version:
	- '2.7'
	- '3.0'

	steps:
	- uses: actions/checkout@v2
	- name: Set up Ruby
	# To automatically get bug fixes and new Ruby versions for ruby/setup-ruby,
	# change this to (see https://github.com/ruby/setup-ruby#versioning):
	# uses: ruby/setup-ruby@v1
	uses: ruby/setup-ruby@473e4d8fe5dd94ee328fdfca9f8c9c7afc9dae5e
	with:
	ruby-version: ${{ matrix.ruby-version }}
	bundler-cache: true # runs 'bundle install' and caches installed gems automatically
	- name: Install graphviz
	run: sudo apt-get install -y graphviz
	- name: Run tests
	run: bundle exec rspec

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