Code review comment for lp:~rockstar/launchpad/branch-scanner-prep

Hi Paul,

I think the job pruner should be altered somewhat.

At the very least it will fail now as there are more than just branch jobs.

Also we may want to be a little more selective in the deletion and not delete
pending jobs.

If we just have a BranchJob pruner for now, we won't be enforcing our rules on
other jobs.

  review needs-fixing