This primarily benefits CLT-only systems where invoking the `xcodebuild`
wrapper in `/usr/bin` will fail (twice) with the following message:
xcode-select: error: tool 'xcodebuild' requires Xcode, but active
developer directory '/Library/Developer/CommandLineTools' is a command
line tools instance
Closes#198.
Signed-off-by: Martin Afanasjew <martin@afanasjew.de>