Add plot of metallicity difference between active and passive galaxies #403

	# This is a basic workflow to help you get started with Actions

	name: CI

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

	# 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:
	# Formatting check
	formatting:
	# 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@v2

	# Installs required Python modules
	- name: Install Python modules
	run: python3 -m pip install black==22.1.0

	# Runs the formatting script
	- name: Formatting
	run: bash format.sh --check

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