Refactor from async to sync

apps/api/src/app/portfolio/portfolio.service.ts

@@ -318,13 +318,13 @@ export class PortfolioService {
     };
   }
 
-  public async getDividends({
+  public getDividends({
     activities,
     groupBy
   }: {
     activities: Activity[];
     groupBy?: GroupBy;
-  }): Promise<InvestmentItem[]> {
+  }): InvestmentItem[] {
     let dividends = activities.map(({ currency, date, value }) => {
       return {
         date: format(date, DATE_FORMAT),