Lint

Exclude unneeded files from gem package #55

	name: Lint

	on: [pull_request]

	jobs:
	rubocop:
	name: RuboCop

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 0 # fetch everything
	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: 3.0
	- name: Install dependencies
	run: bundle install
	- name: Run RuboCop against BASE..HEAD changes
	run: bundle exec rake rubocop:diff origin/${GITHUB_BASE_REF#*/}

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