a tag (annotated or lightweight), and then only if it can fast-forward
<dst>. By having the optional leading `+`, you can tell Git to update
the <dst> ref even if it is not allowed by default (e.g., it is not a
-fast-forward.) This does *not* attempt to merge <src> into <dst>. See
-EXAMPLES below for details.
+fast-forward.).
+
`tag <tag>` means the same as `refs/tags/<tag>:refs/tags/<tag>`.
+