Add unsubscribe subject

apps/client/src/app/pages/portfolio/holdings/holdings-page.component.ts

@@ -147,7 +147,9 @@ export class HoldingsPageComponent implements OnDestroy, OnInit {
           if (this.user?.settings?.isExperimentalFeatures === true) {
             this.holdings = undefined;
 
-            this.fetchPortfolioDetails().subscribe((portfolioDetails) => {
+            this.fetchPortfolioDetails()
+              .pipe(takeUntil(this.unsubscribeSubject))
+              .subscribe((portfolioDetails) => {
                 this.portfolioDetails = portfolioDetails;
 
                 this.initialize();