Since I1094a2be we now treat Push Annotated/Signed Tag as allowing creation of a tag pointing to an existing commit object. The analogous permission for lightweight tags is Create on the reference. It was inconsistent to disallow creating lightweight tags in refs/tags/*, so fix AllProjectsCreator to allow this. Change-Id: Ia115fadee37fa2e7dbea5df49faf3c9f28fe8718