Fix DailyBalanceService query return type.

src/accounts/dailyBalance.service.ts

@@ -13,7 +13,7 @@ export class DailyBalanceService {
     private restangular: Restangular
   ) {}
 
-  query(id: number): Observable<DailyBalance> {
+  query(id: number): Observable<DailyBalance[]> {
     return this.restangular.one('account', id).one('daily_balances').getList();
   }
 }