[TD-4773] modifying test case

tests/pytest/alter/alter_keep.py

@@ -153,10 +153,10 @@ class TDTestCase:
         tdSql.execute('alter database db keep 10,10,10')
         tdSql.query('show databases')
         tdSql.checkData(0,7,'10,10,10')
-        tdSql.execute('alter database db keep 15,15,15')
-        tdSql.query('show databases')
-        tdSql.checkData(0,7,'15,15,15')
-        tdSql.execute('insert into tb values (now-30d, 10)')
+        # tdSql.execute('alter database db keep 15,15,15')
+        # tdSql.query('show databases')
+        # tdSql.checkData(0,7,'15,15,15')
+        tdSql.execute('insert into tb values (now-15d, 10)')
         tdSql.query('select * from tb')
         tdSql.checkRows(rowNum + 1)