igonre the duplicate error when to insert project_blobs on quota syncing

Signed-off-by: wang yan <wangyan@vmware.com>

src/core/api/quota/registry/registry.go

@@ -284,6 +284,9 @@ func persistPB(projects []quota.ProjectInfo) error {
 		}
 		_, err = dao.AddBlobsToProject(pro.ProjectID, blobsOfPro...)
 		if err != nil {
+			if err == dao.ErrDupRows {
+				continue
+			}
 			log.Error(err)
 			return err
 		}