Error with homebrew on linux (linuxbrew)

[benjja]

Warning: Calling `MacOS.version` on Linux is deprecated! There is no replacement.
Please report this issue to the wpscanteam/tap tap (not Homebrew/brew or Homebrew/homebrew-core):
  /home/linuxbrew/.linuxbrew/Homebrew/Library/Taps/wpscanteam/homebrew-tap/Formula/wpscan.rb:16

I get this warning on everything I do with homebrew, not just actions related to wpscan.

[alexsanford]

Thanks for the report! Looks like we need to use the on_macos function for this block so that it doesn't run on linux (ref).