Add rubocop-rake and rubocop-rspec, fix more warnings #14

	name: Lint & Test

	on: push

	jobs:
	test:
	name: Test
	runs-on: ubuntu-latest
	strategy:
	matrix:
	ruby:
	- 2.7.8
	- 3.0.6
	- 3.1.4
	appraisal:
	- rails-5.2
	- rails-6.0
	- rails-6.1
	exclude:
	- ruby: 3.0.6
	appraisal: rails-5.2
	- ruby: 3.1.4
	appraisal: rails-5.2
	steps:
	- name: Install system dependencies
	run: sudo apt-get install -y libsqlite3-dev
	- uses: actions/checkout@master
	- name: Setup ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: ${{ matrix.ruby }}
	- name: Install bundle
	run: bundle
	- name: Install appraisal
	run: bundle exec appraisal install
	- name: Run tests
	run: bundle exec appraisal ${{ matrix.appraisal }} rspec
	lint:
	name: Lint
	runs-on: ubuntu-latest
	steps:
	- name: Install system dependencies
	run: sudo apt-get install -y libsqlite3-dev
	- uses: actions/checkout@master
	- name: Setup ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: 2.7.8
	- name: Install bundle
	run: bundle
	- name: Run rubocop
	run: bundle exec rubocop

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