s3tables: return 404 in handleDeleteNamespace if namespace not found

weed/s3api/s3tables/handler_namespace.go

@@ -383,10 +383,12 @@ func (h *S3TablesHandler) handleDeleteNamespace(w http.ResponseWriter, r *http.R
 	})
 
 	if err != nil {
-		if !errors.Is(err, filer_pb.ErrNotFound) {
+		if errors.Is(err, filer_pb.ErrNotFound) {
+			h.writeError(w, http.StatusNotFound, ErrCodeNoSuchNamespace, fmt.Sprintf("namespace %s not found", flattenNamespace(req.Namespace)))
+		} else {
 			h.writeError(w, http.StatusInternalServerError, ErrCodeInternalError, fmt.Sprintf("failed to list namespace entries: %v", err))
-			return err
 		}
+		return err
 	}
 
 	if hasChildren {