Tests: Verify that validity info is present in cert-show and cert-find command

https://fedorahosted.org/freeipa/ticket/6419

Reviewed-By: Martin Basti <mbasti@redhat.com>

ipatests/test_xmlrpc/test_cert_plugin.py

@@ -229,6 +229,8 @@ class test_cert(BaseCert):
         """
         res = api.Command['cert_show'](sn)['result']
         assert 'cacn' in res
+        assert 'valid_not_before' in res
+        assert 'valid_not_after' in res
 
     def test_0009_cert_find(self):
         """
@@ -237,6 +239,8 @@ class test_cert(BaseCert):
         res = api.Command['cert_find'](min_serial_number=sn,
                                        max_serial_number=sn)['result'][0]
         assert 'cacn' in res
+        assert 'valid_not_before' in res
+        assert 'valid_not_after' in res
 
     def test_00010_cleanup(self):
         """