fix request #5531 - Problem deleting Gerrit Server

Change-Id: I58e6c1bf7469876157a3f96a308a33ef92c9b367
Merge commit 'refs/changes/04/1404/2' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  fix request #5531 - Problem deleting Gerrit Server

Change-Id: I5e18737999746515e5e4494a07d09c1bda54c6aa
Tuleap 6.6.99.26

Change-Id: I082293d5758b9281fb68852178f77ccdb402ac4a