Fix error, submission, hints and help views

spec/factories/error.rb

@@ -1,5 +1,5 @@
 FactoryBot.define do
-  factory :error, class: Error do
+  factory :error, class: CodeOcean::Error do
     association :execution_environment, factory: :ruby
     message { "exercise.rb:4:in `<main>': undefined local variable or method `foo' for main:Object (NameError)" }
   end

spec/models/error_spec.rb

@@ -1,6 +1,6 @@
 require 'rails_helper'
 
-describe Error do
+describe CodeOcean::Error do
   let(:error) { described_class.create }
 
   it 'validates the presence of an execution environment' do