Galera test sporadic failure on galera.galera_var_notify_cmd

2020-01-02T03:57:38.2442720Z galera.galera_var_notify_cmd 'innodb'    w1 [ fail ]

2020-01-02T03:57:38.2444977Z         Test ended at 2020-01-02 03:57:38

2020-01-02T03:57:38.2445482Z 

2020-01-02T03:57:38.2445863Z CURRENT_TEST: galera.galera_var_notify_cmd

2020-01-02T03:57:38.2446538Z --- /__w/1/s/mysql-test/suite/galera/r/galera_var_notify_cmd.result	2020-01-02 01:05:20.000000000 +0000

2020-01-02T03:57:38.2447313Z +++ /__w/1/s/mysql-test/suite/galera/r/galera_var_notify_cmd.reject	2020-01-02 03:57:37.970019059 +0000

2020-01-02T03:57:38.2447979Z @@ -8,4 +8,4 @@

2020-01-02T03:57:38.2448383Z  2

2020-01-02T03:57:38.2448895Z  SELECT COUNT(DISTINCT idx) FROM mtr_wsrep_notify.status;

2020-01-02T03:57:38.2449263Z  COUNT(DISTINCT idx)

2020-01-02T03:57:38.2450401Z -1

2020-01-02T03:57:38.2450880Z +2

2020-01-02T03:57:38.2451202Z 

2020-01-02T03:57:38.2451580Z mysqltest: Result content mismatch