Don't use external youtube resources in test

Resolves https://github.com/openSUSE/osem/issues/1986

spec/spec_helper.rb

@@ -63,7 +63,12 @@ RSpec.configure do |config|
   Capybara.javascript_driver = :poltergeist
 
   Capybara.register_driver :poltergeist do |app|
-    Capybara::Poltergeist::Driver.new(app, phantomjs: Phantomjs.path, js_errors: false, window_size: [1920, 1080])
+    Capybara::Poltergeist::Driver.new(
+      app,
+      phantomjs:   Phantomjs.path,
+      js_errors:   false,
+      window_size: [1920, 1080]
+    )
   end
 
   # Includes helpers and connect them to specific types of tests

spec/support/external_request.rb

@@ -11,9 +11,9 @@ end
 def mock_commercial_request
   response = {
     author_name: 'Confreaks',
-    html: '<iframe width=\'560\' height=\'315\' src=\'https://www.youtube.com/embed/BTTygyxuGj8?feature=oembed\' frameborder=\'0\' allowfullscreen></iframe>',
+    html: '<iframe width="560" height="315" frameborder="0" allowfullscreen></iframe>',
     thumbnail_width: 480,
-    thumbnail_url: 'https://i.ytimg.com/vi/BTTygyxuGj8/hqdefault.jpg',
+    thumbnail_url: '/images/rails.png',
     provider_name: 'YouTube',
     width: 459,
     type: 'video',