Drop GlusterFS jobs

These jobs were removed from manila[1], because the drivers were
deprecated.

The job definitions are still kept to be used in stable branches.

[1] a50f699d449ac286c9ea4a9617abf8fc60845f2e

Change-Id: I5a1126f1c0a9c0f0d83569b5c4de37e1ecdbfca4
1 file changed