[SecuritySolution][Threat Hunting Investigation] Fix timeline showing…

… as changed when it wasn't actually changed (#188106)

## Summary

Fixes elastic/security-team#9646

The embedded discover's `update` mechanism has changed and the `grid`
and `hideChart` properties keep changing on initial sync, causing the
timeline show as `changed` when it actually didn't. These two properties
are not important to actually determine the changed state of timeline
and we can therefore ignore them.

x-pack/plugins/security_solution/public/timelines/components/timeline/tabs/esql/utils/index.ts

@@ -24,8 +24,6 @@ export const savedSearchComparator = (
 
   const keysToSelect = [
     'columns',
-    'grid',
-    'hideChart',
     'sort',
     'timeRange',
     'fields.filter',