ipatests: use whole date for journalctl --since

When a test is executed around midnight and is checking the
journal content with --since=date, it needs to specify the
whole date (with day and time) to avoid missing entries.

If for instance --since=23:59:00 is used and the current time is
now 00:01:00, --since=23:59:00 would refer to a date in the
future and no journal entry will be found.

Fixes: https://pagure.io/freeipa/issue/8953
Reviewed-By: Stanislav Levin <slev@altlinux.org>
Reviewed-By: François Cami <fcami@redhat.com>

ipatests/test_integration/test_commands.py

@@ -1208,7 +1208,8 @@ class TestIPACommand(IntegrationTest):
         # start to look at logs a bit before "now"
         # https://pagure.io/freeipa/issue/8432
         since = time.strftime(
-            '%H:%M:%S', (datetime.now() - timedelta(seconds=10)).timetuple()
+            '%Y-%m-%d %H:%M:%S',
+            (datetime.now() - timedelta(seconds=10)).timetuple()
         )
 
         password = 'WrongPassword'