Implements right "see confidential course" on method findByPerson

Add unit tests for that

src/Bundle/ChillMainBundle/Security/Authorization/AuthorizationHelperForCurrentUserInterface.php

@@ -25,7 +25,8 @@ interface AuthorizationHelperForCurrentUserInterface
     public function getReachableCenters(string $role, ?Scope $scope = null): array;
 
     /**
-     * @param array|Center|Center[] $center
+     * @param list<Center>|Center $center
+     * @return list<Scope>
      */
-    public function getReachableScopes(string $role, $center): array;
+    public function getReachableScopes(string $role, array|Center $center): array;
 }