Add a WIP spec for clearing the cache

spec/lib/gitlab/database/rename_reserved_paths_migration/namespaces_spec.rb

@@ -126,6 +126,8 @@ describe Gitlab::Database::RenameReservedPathsMigration::Namespaces, :truncate d
 
       subject.rename_namespace(namespace)
     end
+
+    it 'invalidates the markdown cache of related projects'
   end
 
   describe '#rename_namespaces' do

spec/lib/gitlab/database/rename_reserved_paths_migration/projects_spec.rb

@@ -59,6 +59,8 @@ describe Gitlab::Database::RenameReservedPathsMigration::Projects, :truncate do
 
       subject.rename_project(project)
     end
+
+    it 'invalidates the markdown cache of related projects'
   end
 
   describe '#move_repository' do