Update externals #179

	# Name of the workflow
	name: flake8

	# Controls when the action will run. Triggers the workflow on push or pull request
	# events but only for the main and stable branches
	on:
	push:
	branches: [ main, stable ]
	pull_request:
	branches: [ main, stable ]

	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	# Main building and testing
	build-test:
	# 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 our repository under $GITHUB_WORKSPACE, so our job can access it
	- uses: actions/checkout@v2
	with:
	submodules: recursive

	# Sets up useful environment variables
	- name: Setup environment variables
	run: \|
	echo "DIMAGE=hepsoftwarefoundation/u20-dev" >> $GITHUB_ENV
	env:
	PLATFORM: u20-dev

	# Pulls the associated Docker image
	- name: Docker pull
	run: docker pull $DIMAGE

	# Builds the code and runs the test
	- name: Flake8 Lint
	run: docker run -v $(pwd):/mnt $DIMAGE /mnt/.github/scripts/flake8.sh

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