dispatcher/approver-fails.py: remove a race condition
dispatcher/approver-fails.py: remove a race condition

We can't assert that there are no more dispatch operations until the one
we had has signalled Finished.

freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control