Recurring ORA-12012, ORA-20001, ORA-06512 In Container Database

SYMPTOMS
In container database, following errors are seen in the alert log:
ORA-12012: error on auto execute of job "SYS"."ORA$AT_OS_OPT_SY_7165"
ORA-20001: Statistics Advisor: Invalid task name for the current user
ORA-06512: at "SYS.DBMS_STATS", line 47207
ORA-06512: at "SYS.DBMS_STATS_ADVISOR", line 882
ORA-06512: at "SYS.DBMS_STATS_INTERNAL", line 20059
ORA-06512: at "SYS.DBMS_STATS_INTERNAL", line 22201
ORA-06512: at "SYS.DBMS_STATS", line 47197


CAUSE
This is due to following unpublished bug:
Bug 22879263 - BETA 12.2 - ORA-12012 , ORA-20001 AND ORA-06512 FROM ORA$AT_OS_OPT_SY_88 JOB

SOLUTION
Bug is fixed in 12.2.0.1.0.
Use following workaround:
execute "EXEC dbms_stats.init_package();"