Fix shared runners minutes

What does this MR do?

Fix shared runners minutes

Update only projects with used allowance, not all. We have millions of projects, and only a small portion of them use CI.

This is not ideal solution, as we should start using a new row, but before we change how builds are picked this is probably the fix.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/33213

cc @zj