fix(lib): resolve type errors

libs/ui/src/lib/accounts-table/accounts-table.component.ts

@@ -77,7 +77,7 @@ export class GfAccountsTableComponent implements OnChanges, OnDestroy {
   @ViewChild(MatSort) sort: MatSort;
 
   public dataSource = new MatTableDataSource<Account>();
-  public displayedColumns = [];
+  public displayedColumns: string[] = [];
   public isLoading = true;
   public routeQueryParams: Subscription;
 

libs/ui/src/lib/toggle/toggle.component.ts

@@ -26,13 +26,15 @@ export class GfToggleComponent implements OnChanges {
 
   @Output() valueChange = new EventEmitter<Pick<ToggleOption, 'value'>>();
 
-  public optionFormControl = new FormControl<string>(undefined);
+  public optionFormControl = new FormControl<string | null>(null);
 
   public ngOnChanges() {
     this.optionFormControl.setValue(this.defaultValue);
   }
 
   public onValueChange() {
+    if (this.optionFormControl.value !== null) {
       this.valueChange.emit({ value: this.optionFormControl.value });
     }
   }
+}