Remove `to_s` from some `Pathname`s.

Library/Homebrew/brew.rb

Library/Homebrew/cask/lib/hbc/artifact/relocated.rb

Library/Homebrew/cask/lib/hbc/cli.rb

Library/Homebrew/cmd/style.rb

Library/Homebrew/dev-cmd/audit.rb

Library/Homebrew/diagnostic.rb

Library/Homebrew/extend/os/mac/keg_relocate.rb

Library/Homebrew/tap_constants.rb

Library/Homebrew/test/cmd/--env_spec.rb

Library/Homebrew/test/cmd/--version_spec.rb

...ew/test/support/helper/spec/shared_examples/hbc_staged.rb

Library/Homebrew/utils.rb

Library/Homebrew/utils/github.rb

Library/Homebrew/version.rb