remove garbling spinner

one of the three new spinners produced less than ideal output when a
push happened; the other two do enhance the create experience and i
think we can get away without one for push.

pkg/cmd/pr/create/create.go

@@ -681,9 +681,7 @@ func handlePush(opts CreateOptions, ctx CreateContext) error {
 			return nil
 		}
 
-		opts.IO.StartProgressIndicator()
 		err := pushBranch()
-		opts.IO.StopProgressIndicator()
 		if err != nil {
 			return err
 		}