Remove unnecessary logic from MissingElse
Remove unnecessary logic from MissingElse

Some years ago, the logic for generating the `message` was extracted to
a method, leaving a couple of unnecessary lines behind. See
b11ef7741f38b7c23761695f5b3bcb7a0219dfeb.

tdeo/rubocop,tejasbubane/rubocop,jmks/rubocop,maxjacobson/rubocop,rrosenblum/rubocop,jmks/rubocop,bbatsov/rubocop,tejasbubane/rubocop,bbatsov/rubocop,maxjacobson/rubocop,tdeo/rubocop,jmks/rubocop,rrosenblum/rubocop,tejasbubane/rubocop,rrosenblum/rubocop,maxjacobson/rubocop,tdeo/rubocop