[Authentification] Correction de l'affichage admin sur /light (#2621)

## Linked issues


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- [ ] Tests E2E (Cypress)

frontend/src/hooks/authorization/useGetUserAuthorization.ts

@@ -18,7 +18,7 @@ export function useGetUserAuthorization(): UserAuthorization | undefined {
        * This is used to have backward compatibility with the Apache .htacess authentication (on `/` and `/ext`) while the authentication
        * is not yet activated, as the app is only protected by the entrypoint path.
        */
-      const isExtPage = window.location.pathname === '/ext' || window.location.pathname === '/nav'
+      const isExtPage = window.location.pathname === '/ext' || window.location.pathname === '/light'
 
       setUserAuthorization({
         isLogged: true,