Formatting of a path in README
Formatting of a path in README

Cherry-picked from #578.

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