No need to override core views in backlogs module

The two overridden views were `project_settings/_versions.html.erb` and
`versions/_form.html.erb`, and overridding them is not needed anymore:
- core `project_settings/_versions.html.erb` was renamed in 2be6ca1,
  and the one from backlogs module was removed in 9de876d
- backlogs module `versions/_form.html.erb` was removed in 1850622.

modules/backlogs/lib/open_project/backlogs/engine.rb

@@ -120,9 +120,6 @@ def self.settings
            before: :settings_storage
     end
 
-    # We still override version and project settings views from the core! URH
-    override_core_views!
-
     patches %i[PermittedParams
                WorkPackage
                Status