1. Validate options before constraint violations. This allows
us to error out when --cask is passed on Linux before getting
a constraint violation when --cask and --formula are set.
2. Skip printing the help page when --cask is passed on Linux.
- This was done with `brew typecheck --update --suggest-typed` which
(as of the previous commit) uses Spoom, yet another gem. I thought I'd
see how well it works. There are no Sorbet errors after these changes!