Move PushUpdate dependency from models to repofiles (#6763)

* remove push_update

* move models.PushUpdate to repofiles.PushUpdate

modules/repofiles/upload.go

@@ -188,7 +188,8 @@ func UploadRepoFiles(repo *models.Repository, doer *models.User, opts *UploadRep
 	if err = repo.GetOwner(); err != nil {
 		return fmt.Errorf("GetOwner: %v", err)
 	}
-	err = models.PushUpdate(
+	err = PushUpdate(
+		repo,
 		opts.NewBranch,
 		models.PushUpdateOptions{
 			PusherID:     doer.ID,
@@ -203,7 +204,6 @@ func UploadRepoFiles(repo *models.Repository, doer *models.User, opts *UploadRep
 	if err != nil {
 		return fmt.Errorf("PushUpdate: %v", err)
 	}
-	// FIXME: Should we models.UpdateRepoIndexer(repo) here?
 
 	return models.DeleteUploads(uploads...)
 }