[ObsUX] Fix error when navigating from infra to other apps (#170564)

fixes https://github.com/elastic/kibana/issues/170562

## Summary

This PR fixes the error that happens when navigating from infra app to
another app while the charts are still loading


66cecf6d-96e5-4630-b968-aada98b6678a


### How to test

- Navigate to `Infrastructure` > `Hosts`
- While the charts are still loading, navigate to any other app.

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>

x-pack/plugins/infra/public/apps/metrics_app.tsx

@@ -51,6 +51,7 @@ export const renderApp = (
   );
 
   return () => {
+    plugins.data.search.session.clear();
     core.chrome.docTitle.reset();
     ReactDOM.unmountComponentAtNode(element);
   };