request #7371: Remove plugin service icon from core

This shouldn't have any impact at-all on the current Tuleap UI but is needed to make the css of each plugin independant.


Change-Id: I1fb53ee1d323485b13470d918c63b6edc7cae471
Merge commit 'refs/changes/17/2917/3' of ssh://gerrit.tuleap.net:29418/tuleap into HEAD

* ssh://gerrit.tuleap.net:29418/tuleap:
  request #7371: Remove plugin service icon from core

Change-Id: I5a15d12bc7d07bfa1cb4467ef044bb046f08df92
This is Tuleap 7.4.99.0

Change-Id: I277f76610394749c019c2e7cb068c3d8b503ab3a