Bump actions/checkout from 3 to 4 (#70) #7

	---
	# Run this locally with act - https://github.com/nektos/act
	# act -j lintMarkdown
	name: Lint Markdown

	on: # yamllint disable-line rule:truthy
	push:
	branches: [master]
	paths:
	- '**.md'
	- '.github/workflows/lint-markdown.yaml'
	pull_request:
	branches: [master]
	paths:
	- '**.md'
	- '.github/workflows/lint-markdown.yaml'

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	lintMarkdown:
	runs-on: ubuntu-latest
	timeout-minutes: 15

	steps:
	- name: Checkout code
	uses: actions/checkout@v4

	- name: Set up Ruby
	# See https://github.com/ruby/setup-ruby#versioning
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: 3.0

	- name: Install dependencies
	run: gem install mdl

	- name: Run tests
	run: mdl -r ~MD013,~MD029,~MD033 README.md

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