request #7528: Fatal error on gl-admin-housekeeping.php

Change-Id: I5942ceea195261cd8773e463a625613b11b6e21a
Merge commit 'refs/changes/33/3133/1' of ssh://gerrit.tuleap.net:29418/tuleap into HEAD

* ssh://gerrit.tuleap.net:29418/tuleap:
  request #7528: Fatal error on gl-admin-housekeeping.php

Change-Id: I64bcc013f6b9aaa94d9c868ad65e054415d04b3a
This is Tuleap 7.5.99.75

Change-Id: I34e367cfd026de24a974cab624db0762b073a77a