Large undo due to droping task AUTO_STATS_ADVISOR_TASK

Hello,

I just followed steps in  (Doc ID 2305512.1) and executed

DECLARE
v_tname VARCHAR2(32767);
BEGIN
v_tname := 'AUTO_STATS_ADVISOR_TASK';
DBMS_STATS.DROP_ADVISOR_TASK(v_tname);
END;
/

This caused big growth of Undo TBS so I canceled job by clicking Ctrl-C. Now I see that undo consumption was not cleaned up after breaking job (but stopped growing). Should I clean now undo manually or it will be cleaned by Oracle if needed ?