Remove MD5 output from build log

We don't need this step anymore: b984b3ac

This will reduce the amount of time it takes to render the output of build log (as thousands of now "useless" lines will be omitted).

https://dev.gitlab.org/gitlab/omnibus-gitlab/builds/144549 (old)

vs

https://dev.gitlab.org/gitlab/omnibus-gitlab/builds/145189 (now)