Use File.exist?, File.exists? is removed in ruby head (#268)
Use File.exist?, File.exists? is removed in ruby head (#268)

Co-authored-by: Oleg Pudeyev <e6fb06210fafc02fd7479ddbed2d042cc3a5155e@olegp.name>
mongodb/bson-ruby,mongodb/bson-ruby,mongodb/bson-ruby,mongodb/bson-ruby