Trigger webhooks on issue label-change via API too (#10421)

* trigger webhooks with api too

* fix comment

* notify report old too

* CI restart

* restart CI again

* remove duplicated code

services/issue/label.go

@@ -61,3 +61,18 @@ func RemoveLabel(issue *models.Issue, doer *models.User, label *models.Label) er
 	notification.NotifyIssueChangeLabels(doer, issue, nil, []*models.Label{label})
 	return nil
 }
+
+// ReplaceLabels removes all current labels and add new labels to the issue.
+func ReplaceLabels(issue *models.Issue, doer *models.User, labels []*models.Label) error {
+	old, err := models.GetLabelsByIssueID(issue.ID)
+	if err != nil {
+		return err
+	}
+
+	if err := issue.ReplaceLabels(labels, doer); err != nil {
+		return err
+	}
+
+	notification.NotifyIssueChangeLabels(doer, issue, labels, old)
+	return nil
+}