chore: add type signatures and type checker for CI #170

	name: CI

	on:
	- push
	- pull_request

	jobs:
	rspec:
	runs-on: ${{ matrix.os }}
	name: Ruby ${{ matrix.ruby }} on ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	os:
	- ubuntu-latest
	# NOTE: hold off testing other platforms until we start having native dependencies or running into issues on them
	# - macos-latest
	# - windows-latest
	ruby:
	- "2.7"
	- "3.0"
	- "3.1"
	- "3.2"
	env:
	BUNDLE_GEMFILE: Gemfile

	steps:
	- uses: actions/checkout@v3
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: ${{ matrix.ruby }}
	- run: bundle install
	- name: RSpec
	run: bundle exec rspec
	rubocop:
	name: Rubocop
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: 3.2
	- run: bundle install
	- name: Rubocop
	run: bundle exec rubocop --color
	steep:
	runs-on: ubuntu-latest
	name: Steep
	steps:
	- uses: actions/checkout@v3
	- uses: ruby/setup-ruby@v1
	with:
	ruby-version: 3.2
	- run: bundle install
	- name: Steep
	run: bundle exec steep check
	# check the status of other jobs, so we can have a single job dependency for branch protection
	# https://github.com/community/community/discussions/4324#discussioncomment-3477871
	status:
	name: CI Status
	runs-on: ubuntu-latest
	needs: [rspec, rubocop]
	if: always()
	steps:
	- name: Successful CI
	if: ${{ !(contains(needs.*.result, 'failure')) }}
	run: exit 0
	- name: Failing CI
	if: ${{ contains(needs.*.result, 'failure') }}
	run: exit 1

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