We rely on this image in many of our system-config-run-* jobs to
interact with services through firefox and take screenshots of them
within the browser. Continue to reduce our reliance on docker hub by
mirroring this image to quay.io.
A followup will update the run-selenium role in this repo to run the
image from quay.io instead.
Change-Id: I4c923291e7f4b5d275a6ff48210b935edf837e70