fix(observables): http cancellable Subject should be unsubscribed

Author: ghiscoding

src/app/modules/angular-slickgrid/services/filter.service.ts

@@ -100,6 +100,7 @@ export class FilterService {
     }
     if (isObservable(this.httpCancelRequests$)) {
       this.httpCancelRequests$.next(); // this cancels any pending http requests
+      this.httpCancelRequests$.unsubscribe();
     }
     this.disposeColumnFilters();
     this._onSearchChange = null;

src/app/modules/angular-slickgrid/services/sort.service.ts

@@ -187,6 +187,7 @@ export class SortService {
     }
     if (isObservable(this.httpCancelRequests$)) {
       this.httpCancelRequests$.next(); // this cancels any pending http requests
+      this.httpCancelRequests$.unsubscribe();
     }
   }