story #7511: temporary fix loading of ui-tree css

Change-Id: I132f8dd6bb133c768e01ec4a74c3a9511044c908
Merge commit 'refs/changes/57/3357/2' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  story #7511: temporary fix loading of ui-tree css

Change-Id: If6b54d6fadea6cd987a86d13943023c50bc4b58a
This is Tuleap 7.7.99.82

Change-Id: Id82cb503416a846dc1ef6f187a4dc7443dc65f68