Remove the GitProbe from the gitlab-monitor config

This setting was not working properly as is, and gitlab-monitor expects you to configure a list of git repositories. And the push probe will commit to the repository.

Closes: https://gitlab.com/gitlab-org/omnibus-gitlab/issues/2602

cc @bjk-gitlab

unmarked as a Work In Progress

assigned to @marin

probe was enabled, was wasn't being hit I think. Which is why we haven't seen the error. I ran a branch with the git probe removed and it seemed fine.

approved this merge request

LGTM

changed milestone to %9.5

merged

mentioned in commit fcfc3dd2