Homebrew reports 'Found Ruby file outside tobi/try tap formula directory'

`try` installed on macOS using `homebrew`. `brew doctor` reports:

```
Warning: Found Ruby file outside tobi/try tap formula directory.
(/opt/homebrew/Library/Taps/tobi/homebrew-try/Formula):
  /opt/homebrew/Library/Taps/tobi/homebrew-try/try.rb
```