Move change issue title from models to issue service package (#8456)

* move change issue title from models to issue service package

* make the change less

* fix typo

models/issue_test.go

@@ -160,7 +160,7 @@ func TestUpdateIssueCols(t *testing.T) {
 	issue.Content = "This should have no effect"
 
 	now := time.Now().Unix()
-	assert.NoError(t, UpdateIssueCols(issue, "name"))
+	assert.NoError(t, updateIssueCols(x, issue, "name"))
 	then := time.Now().Unix()
 
 	updatedIssue := AssertExistsAndLoadBean(t, &Issue{ID: issue.ID}).(*Issue)