The typheous Faraday Middleware emits a circular dep warning

[olleolleolle]

Basic Info

• Faraday Version: 1.0.1
• Ruby Version: any

Issue description

The typheous middleware emits a circular dependency warning.

Stacktrace

/home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/dependency_loader.rb:11: warning: /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/dependency_loader.rb:11: warning: loading in progress, circular require considered harmful - /home/travis/build/typhoeus/typhoeus/lib/typhoeus/adapters/faraday.rb
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/exe/rspec:4:in  `<main>'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/runner.rb:45:in  `invoke'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/runner.rb:71:in  `run'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/runner.rb:86:in  `run'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/runner.rb:102:in  `setup'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/configuration.rb:1581:in  `load_spec_files'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/configuration.rb:1581:in  `each'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/configuration.rb:1583:in  `block in load_spec_files'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/configuration.rb:2076:in  `load_file_handling_errors'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/rspec-core-3.9.1/lib/rspec/core/configuration.rb:2076:in  `load'
	from /home/travis/build/typhoeus/typhoeus/spec/typhoeus/adapters/faraday_spec.rb:3:in  `<top (required)>'
	from /home/travis/build/typhoeus/typhoeus/spec/typhoeus/adapters/faraday_spec.rb:3:in  `require'
	from /home/travis/build/typhoeus/typhoeus/lib/typhoeus/adapters/faraday.rb:3:in  `<top (required)>'
	from /home/travis/build/typhoeus/typhoeus/lib/typhoeus/adapters/faraday.rb:4:in  `<module:Faraday>'
	from /home/travis/build/typhoeus/typhoeus/lib/typhoeus/adapters/faraday.rb:21:in  `<class:Adapter>'
	from /home/travis/build/typhoeus/typhoeus/lib/typhoeus/adapters/faraday.rb:21:in  `require'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/adapter/typhoeus.rb:3:in  `<top (required)>'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/adapter/typhoeus.rb:4:in  `<module:Faraday>'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/adapter/typhoeus.rb:7:in  `<class:Adapter>'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/adapter/typhoeus.rb:12:in  `<class:Typhoeus>'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/dependency_loader.rb:11:in  `dependency'
	from /home/travis/.rvm/gems/ruby-2.6.4/gems/faraday-1.0.0/lib/faraday/dependency_loader.rb:11:in  `require'

It seems like https://github.com/typhoeus/typhoeus/blob/master/lib/typhoeus/adapters/faraday.rb#L21 triggers a class-loading of the adapter in Faraday, which in turns reloads the typhoeus adapter.

Steps to reproduce

Example of what it looks like in the wild:
https://travis-ci.org/github/typhoeus/typhoeus/jobs/658867808#L264