incompatibilities with hashie 3.5.5

[375gnu]

Failures:

  1) Buff::Config::Ruby#to_rb returns ruby with key values for each attribute
     Failure/Error: expect(lines[3]).to eq('cookbook_path(["cookbooks"])')

       expected: "cookbook_path([\"cookbooks\"])"
            got: "cookbook_path(#<Hashie::Array [\"cookbooks\"]>)"

       (compared using ==)
     # ./spec/buff/config/ruby_spec.rb:90:in `block (3 levels) in <top (required)>'

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30 examples, 1 failure

Failed examples:

rspec ./spec/buff/config/ruby_spec.rb:79 # Buff::Config::Ruby#to_rb returns ruby with key values for each attribute