Since version 8.7.0-bb.0, an image that is not publicly available is in images.txt

Starting with version 8.7.0-bb.0 an image registry1.dso.mil/bigbang-ci/gitlab-tester is included in images.txt, but this image is unavailable.

Should all the images in images.txt be able to be pulled?

I found this related ticket from one year ago: #178 (closed)