cherry-pick [Upgrade][SQL]Modify the table t_ds_worker_group to add a description field in the postgresql upgrade script #12883

dolphinscheduler-dao/src/main/resources/sql/upgrade/3.1.1_schema/postgresql/dolphinscheduler_ddl.sql

@@ -15,4 +15,4 @@
  * limitations under the License.
 */
 --- add column
-ALTER TABLE t_ds_task_group alter COLUMN description type varchar(255);
+ALTER TABLE t_ds_worker_group ADD COLUMN IF NOT EXISTS description varchar(255) DEFAULT NULL;