fix(backend): clean unused var in admin.service.ts

backend/src/admin/admin.service.ts

@@ -184,7 +184,7 @@ export class AdminService {
           (acc, curr) => acc + (Number(curr.totalAmount) || 0),
           0,
         ) || 0;
-      const { orders, ...rest } = u;
+      const { orders: _orders, ...rest } = u;
       return {
         ...rest,
         totalSpent,