Bump actions/checkout from 3 to 4 (#23) #9

	---
	name: Lint Dockerfiles

	on: # yamllint disable-line rule:truthy
	push:
	branches: [main, master]
	paths:
	- "**/Dockerfile"
	- ".github/workflows/lint-docker.yaml"
	pull_request:
	branches: [main, master]
	paths:
	- "**/Dockerfile"
	- ".github/workflows/lint-docker.yaml"

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

	jobs:
	# Run this locally with act - https://github.com/nektos/act
	# act -j lintDocker
	lintDocker:
	runs-on: ubuntu-latest
	timeout-minutes: 15

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

	# To lint multiple docker files
	# Ref: https://github.com/hadolint/hadolint-action/issues/54#issuecomment-1130157411
	- name: Install hadolint
	run: \|
	docker pull hadolint/hadolint:latest
	container_id=$(docker create hadolint/hadolint)
	docker cp $container_id:/bin/hadolint .

	- name: Run hadolint
	run: \|
	./hadolint --ignore DL3007 --ignore DL3008 --ignore DL3013 --ignore DL3018 $(find . -iname Dockerfile)

Provide feedback