Fix help for block UI.
Fix help for block UI.

google/codeworld,alphalambda/codeworld,tgdavies/codeworld,google/codeworld,pranjaltale16/codeworld,pranjaltale16/codeworld,tgdavies/codeworld,google/codeworld,alphalambda/codeworld,pranjaltale16/codeworld,alphalambda/codeworld,tgdavies/codeworld