Bump Ruby to 2.6.5 in omnibus-gitlab tester images
Related to https://gitlab.com/gitlab-org/omnibus-gitlab/issues/4658. Depends on gitlab!22372 (merged)
Also removes unused images.
Edited by Balasankar 'Balu' C
Related to https://gitlab.com/gitlab-org/omnibus-gitlab/issues/4658. Depends on gitlab!22372 (merged)
Also removes unused images.