fastlane: Fastlane not working on macOS 10.13 (beta 1 or 2)

New Issue Checklist

• Updated fastlane to the latest version
• I have read the Contribution Guidelines

Issue Description

trying to run any fast lane tool gives something like

Floorshow:Weather mh [master]+ $ deliver
/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/2.3.0/rubygems/dependency.rb:319:in `to_specs': Could not find 'deliver' (>= 0) among 37 total gem(s) (Gem::LoadError)
Checked in 'GEM_PATH=/Users/mh/.gem/ruby/2.3.0:/Library/Ruby/Gems/2.3.0:/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/gems/2.3.0', execute `gem env` for more information
	from /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/2.3.0/rubygems/dependency.rb:328:in `to_spec'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/2.3.0/rubygems/core_ext/kernel_gem.rb:65:in `gem'
	from /usr/local/bin/deliver:22:in `<main>'

Environment

doesn’t work either, due to what seems a hardcoded rugby version?

$ fastlane env
-bash: /usr/local/bin/fastlane: /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby: bad interpreter: No such file or directory