On what date did the Brisbane Lions (1) win?
CREATE TABLE "nsl_cup_winners" (
  "season" text,
  "cup_final_date" text,
  "winning_team" text,
  "score" text,
  "losing_team" text,
  "cup_final_attendance" text
);
SELECT "cup_final_date" FROM "nsl_cup_winners" WHERE "winning_team"='brisbane lions (1)';