Update workflow to use the public Docker image. (#14) #9

	name: Validate WDL workflow and task definitions

	# Controls when the workflow will run
	on:
	# Triggers the workflow on push or pull request events but only for the "main" branch
	push:
	branches: [ "main" ]
	pull_request:
	branches: [ "main" ]

	# Allows you to run this workflow manually from the Actions tab
	workflow_dispatch:

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	# This workflow contains a single job called "build"
	build:
	# The type of runner that the job will run on
	runs-on: ubuntu-latest

	# Steps represent a sequence of tasks that will be executed as part of the job
	steps:
	# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
	- uses: actions/checkout@v3

	# Runs a set of commands using the runners shell
	- name: Validate WDL
	run: \|
	set -o xtrace
	set -o errexit
	set -o pipefail
	set -o nounset

	sudo apt-get install shellcheck
	pip install miniwdl

	for WDL_FILE in $(find . -type f -name "*.wdl"); do
	miniwdl check ${WDL_FILE}
	done

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