Merge branch 'fix-1821' of https://git.openi.org.cn/OpenI/aiforge into fix-1821

models/issue.go

@@ -779,6 +779,9 @@ func (issue *Issue) ChangeContent(doer *User, content string) (err error) {
 func (issue *Issue) ChangeRef(doer *User, newRef string) (err error) {
 	oldRef := issue.Ref
 	issue.Ref = newRef
+	if oldRef == newRef {
+		return nil
+	}
 
 	sess := x.NewSession()
 	defer sess.Close()