Updated Otter-Grader: 5.5.0 #7

	name: Test container image build

	on:
	pull_request:

	jobs:
	test-build:
	runs-on: ubuntu-latest
	steps:

	# For biggish images, github actions runs out of disk space.
	# So we cleanup some unwanted things in the disk image, and reclaim that space for our docker use
	# https://github.com/actions/virtual-environments/issues/2606#issuecomment-772683150
	# and https://github.com/easimon/maximize-build-space/blob/b4d02c14493a9653fe7af06cc89ca5298071c66e/action.yml#L104
	# This gives us a total of about 52G of free space, which should be enough for now
	- name: cleanup disk space
	run: \|
	sudo rm -rf /usr/local/lib/android /usr/share/dotnet /opt/ghc
	df -h

	- name: checkout files in repo
	uses: actions/checkout@main

	- name: Build the image and push it if `NO_PUSH` disabled
	uses: jupyterhub/repo2docker-action@master
	with:
	NO_PUSH: "true"
	DOCKER_REGISTRY: "quay.io"
	# Put repo contents in /srv/repo, rather than the default (/home/jovyan). The home directory
	# is mounted over by persistent storage when we are using the built image in a JupyterHub, and
	# so all contents put in /home/jovyan are lost. This particularly prevents any 'start' script from
	# working, as it is needed in runtime.
	REPO_DIR: /srv/repo

	# Lets us monitor disks getting full as images get bigger over time
	- name: Show how much disk space is left
	run: df -h

Provide feedback