Add topics for repository API (#31127)

Fix ##31100

services/convert/repository.go

@@ -236,6 +236,7 @@ func innerToRepo(ctx context.Context, repo *repo_model.Repository, permissionInR
 		MirrorInterval:                mirrorInterval,
 		MirrorUpdated:                 mirrorUpdated,
 		RepoTransfer:                  transfer,
+		Topics:                        repo.Topics,
 		ObjectFormatName:              repo.ObjectFormatName,
 	}
 }