fix(测试计划): 测试计划子计划查询时增加计划起止时间的查询

--bug=1042548 --user=宋天阳 【测试计划】编辑计划的计划起止时间失败 https://www.tapd.cn/55049933/s/1535965

backend/services/test-plan/src/main/java/io/metersphere/plan/mapper/ExtTestPlanMapper.xml

@@ -74,9 +74,11 @@
         t.module_id as moduleId,
         t.type,
         t.description,
+        t.pos,
         t.actual_start_time AS actualStartTime,
         t.actual_end_time AS actualEndTime,
-        t.pos,
+        t.planned_start_time AS plannedStartTime,
+        t.planned_end_time AS plannedEndTime,
         t.group_id AS parent,
         t.tags
         FROM test_plan t