[Lens] Stabilize FTR test (elastic#202476)

## Summary

Fixes elastic#200120

The navigation bar is not focused for some reason. Making it wait a bit
seems to stabilize it.

### Checklist

- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

(cherry picked from commit 9df7373)

# Conflicts:
#	x-pack/test/functional/apps/lens/group2/persistent_context.ts

x-pack/test/functional/apps/lens/group2/persistent_context.ts

@@ -5,7 +5,7 @@
  * 2.0.
  */
 
-import expect from '@kbn/expect';
+import expect from '@kbn/expect/expect';
 import { FtrProviderContext } from '../../../ftr_provider_context';
 
 export default function ({ getService, getPageObjects }: FtrProviderContext) {
@@ -75,9 +75,11 @@ export default function ({ getService, getPageObjects }: FtrProviderContext) {
           await listingTable.searchForItemWithName('lnsTableVis');
           await lens.clickVisualizeListItemTitle('lnsTableVis');
           await lens.goToTimeRange();
-          await navigationalSearch.focus();
-          await navigationalSearch.searchFor('type:application lens');
-          await navigationalSearch.clickOnOption(0);
+          await retry.try(async () => {
+            await navigationalSearch.focus();
+            await navigationalSearch.searchFor('type:application lens');
+            await navigationalSearch.clickOnOption(0);
+          });
           await lens.waitForEmptyWorkspace();
           await lens.switchToVisualization('lnsLegacyMetric');
           await lens.dragFieldToWorkspace('@timestamp', 'legacyMtrVis');