fix(logout): fix frontend logout function for firefox clients

Previous implementation of logout(), with routing to login page after asynchronous request to backend /auth/logout endpoint, would not work on every client.
Also, while still functional on Chrome clients, the previous implementation was weird as one would get redirected to the login page while possibly not yet fully logged out.

This new implementation executes routing to login page after backend logout is done.

frontend/src/app/components/auth/auth.service.ts

@@ -137,14 +137,12 @@ export class AuthService {
     this.cruvedService.clearCruved();
     // call the logout route to delete the session
     this._http.get<any>(`${this.config.API_ENDPOINT}/auth/logout`).subscribe(() => {
-      location.reload();
+      if (this.config.CAS_PUBLIC.CAS_AUTHENTIFICATION) {
+        document.location.href = `${this.config.CAS_PUBLIC.CAS_URL_LOGOUT}?service=${this.config.URL_APPLICATION}`;
+      } else {
+        this.router.navigate(['/login']);
+      }
     });
-
-    if (this.config.CAS_PUBLIC.CAS_AUTHENTIFICATION) {
-      document.location.href = `${this.config.CAS_PUBLIC.CAS_URL_LOGOUT}?service=${this.config.URL_APPLICATION}`;
-    } else {
-      this.router.navigate(['/login']);
-    }
   }
 
   private cleanLocalStorage() {