Update rspec to last version

spec/producer/core/remote_spec.rb

@@ -71,7 +71,8 @@ module Producer::Core
       let(:sftp_session) { double 'sftp session' }
 
       it 'returns an FS instance built with a new sftp session' do
-        remote.stub_chain(:session, :sftp, :connect) { sftp_session }
+        allow(remote)
+          .to receive_message_chain(:session, :sftp, :connect) { sftp_session }
         expect(remote.fs.sftp).to be sftp_session
       end
     end

spec/spec_helper.rb

@@ -4,8 +4,6 @@ Dir['spec/support/**/*.rb'].map { |e| require e.gsub 'spec/', '' }
 
 
 RSpec.configure do |c|
-  c.treat_symbols_as_metadata_keys_with_true_values = true
-
   c.include TestEnvHelpers, :env
 
   c.include NetSSHStoryHelpers, :ssh