Add new spec for validation_errors

This extra expectation ensures that `validation_errors[:any_key]` also
won't throw an error.

Author: happycollision

spec/helpers_spec.rb

@@ -199,6 +199,7 @@
       let(:json) { show_json }
       it 'does not raise an error of its own' do
         expect{ validation_errors }.not_to raise_error
+        expect(validation_errors[:any_key_here]).to be_nil
       end
     end
   end