transaction: add starting requirements for JOB_RESTART

While having a Requires= dependency between units, the dependency is started
automatically on "systemctl start", but it's not started on "systemctl
restart".

JOB_RESTART jobs did not pull the dependencies for starting into the
transaction.

https://bugzilla.redhat.com/show_bug.cgi?id=802770

Note that the other bug noted in comment #2 has been fixed already by avoiding
the deletion of anchor jobs.