Quarantine download MR patch and diff test suite

qa/qa/specs/features/browser_ui/3_create/merge_request/view_merge_request_diff_patch_spec.rb

 # frozen_string_literal: true
 
 module QA
-  context 'Create' do
+  # https://gitlab.com/gitlab-org/quality/staging/issues/55
+  context 'Create', :quarantine do
     describe 'Download merge request patch and diff' do
       before(:context) do
         Runtime::Browser.visit(:gitlab, Page::Main::Login)