Don't make new versioned tag when in --edit mode

commit 0abb1fbb4f92ab2f86f764767cec5956e944f1bb made
"git publish --edit" always create a new versioned tag. Fix it so we
create a new tag only when actually publishing the code.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>