Fix request #7619 Global mediawiki administrator can see content of all private projects

Change-Id: I39560ca67ee263b677f735a384cd05d564db14a9
Merge commit 'refs/changes/34/3234/1' of ssh://gerrit.tuleap.net:29418/tuleap into HEAD

* ssh://gerrit.tuleap.net:29418/tuleap:
  Fix request #7619 Global mediawiki administrator can see content of all private projects

Change-Id: Icbe5da4ee8910beb7afb234d3b0846940027cf3a
This is Tuleap 7.6.99.60

Change-Id: Ib2814deaad6a403406966cea827a0ed40c18aa19