Update documentation regarding tag deletion

The documentation says tags cannot be deleted. This seems not to be
the case.

Change-Id: I3d3838d7468fddf2605f1398ca01c776c03d116c
diff --git a/Documentation/user-upload.txt b/Documentation/user-upload.txt
index 9c656ab..8034637 100644
--- a/Documentation/user-upload.txt
+++ b/Documentation/user-upload.txt
@@ -254,7 +254,7 @@
 * `refs/heads/*`: any branch can be updated, created, deleted,
 or rewritten by the pusher.
 * `refs/tags/*`: annotated tag objects pointing to any other type
-of Git object can be created.  Tags cannot be updated or deleted.
+of Git object can be created.
 
 To push branches, the `Push Branch` project right must be granted
 to one (or more) of the user's groups.  The allowed levels within