Test and fix heroku-20 #20

	name: CI

	on:
	- push
	- pull_request

	jobs:
	lint:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v3
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: 3.1
	bundler-cache: true
	- name: Linting
	run: bundle exec standardrb

	test:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v3
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: '3.1'
	bundler-cache: true
	- name: test
	run: bundle exec rspec spec

	integration_test:
	runs-on: pub-hk-ubuntu-22.04-xlarge
	strategy:
	matrix:
	stack: ["heroku-20", "heroku-22"]
	version: ["3.1.4"]
	steps:
	- name: Checkout
	uses: actions/checkout@v3
	- name: Set up Ruby
	uses: ruby/setup-ruby@ec02537da5712d66d4d50a0f33b7eb52773b5ed1
	with:
	ruby-version: '3.1'
	- name: Install dependencies
	run: bundle install
	- name: Output CHANGELOG
	run: bundle exec rake "changelog[${{matrix.version}}]"
	- name: Build Docker image
	run: bundle exec rake "generate_image[${{matrix.stack}}]"
	- name: Generate Ruby Dockerfile
	run: bundle exec rake "new[${{matrix.version}},${{matrix.stack}}]"
	- name: Build and package Ruby runtime
	run: bash "rubies/${{matrix.stack}}/ruby-${{matrix.version}}.sh"
	- name: Verify ruby executable and output rubygems version
	run: bundle exec rake "rubygems_version[${{matrix.version}},${{matrix.stack}}]"

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