[BUGFIX] Fix ordering of stages in action dropdown

If multiple stages exist and a user is member of only a few stages,
then in many cases the ordering of the stages is mixed up.

Change-Id: Ifab7e0afd412f63de574ef262ad4b982cfe1e5e4
Fixes: #36469
Releases: 6.2, 6.1, 6.0
Reviewed-on: https://review.typo3.org/21107
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Stefan Neufeind
Tested-by: Stefan Neufeind