Update scrutiniser configuration.

.scrutinizer.yml

@@ -39,6 +39,7 @@ checks:
         avoid_fixme_comments: true
         avoid_multiple_statements_on_same_line: true
         align_assignments: true
+        duplication: false
     javascript: true
 
 coding_style:

app/Http/Controllers/PreferencesController.php

@@ -113,6 +113,7 @@ class PreferencesController extends Controller
      * @param TokenFormRequest $request
      *
      * @return \Illuminate\Http\RedirectResponse|\Illuminate\Routing\Redirector
+     * @SuppressWarnings(PHPMD.UnusedFormalParameter) // it's unused but the class does some validation.
      */
     public function postCode(TokenFormRequest $request)
     {