[ui]: fix the undefined check resolving as true for scheduleTask tab (#4256)

Author: ramprasadagarwal

desktop/core/src/desktop/js/apps/jobBrowser/knockout/JobBrowserViewModel.js

@@ -76,7 +76,7 @@ export default class JobBrowserViewModel {
         !this.isMini() && schedulerInterfaceCondition();
 
       const schedulerBeatInterfaceCondition = () =>
-        this.appConfig()?.scheduler?.interpreter_names.indexOf('celery-beat') !== -1;
+        this.appConfig()?.scheduler?.interpreter_names.includes('celery-beat');
 
       const livyInterfaceCondition = () =>
         !this.isMini() &&