workflows/tests: move more macOS tests to Linux.
workflows/tests: move more macOS tests to Linux.

`brew style` is OS independent so let's run all the `brew style` tests
on Linux rather than macOS.

sjackman/homebrew,claui/brew,nandub/brew,JCount/brew,Homebrew/brew,vitorgalvao/brew,vitorgalvao/brew,sjackman/homebrew,MikeMcQuaid/brew,JCount/brew,nandub/brew,MikeMcQuaid/brew,nandub/brew,vitorgalvao/brew,EricFromCanada/brew,EricFromCanada/brew,EricFromCanada/brew,claui/brew,sjackman/homebrew,sjackman/homebrew,EricFromCanada/brew,claui/brew,Homebrew/brew,MikeMcQuaid/brew,JCount/brew,Homebrew/brew,MikeMcQuaid/brew,JCount/brew,nandub/brew,Homebrew/brew,vitorgalvao/brew,claui/brew