[Data Explorer][Discover 2.0] Allow Top Nav to update based on index …

…pattern change (#4889) (#4899)

Issue Resolve
#4888


(cherry picked from commit c886b00)

Signed-off-by: ananzh <ananzh@amazon.com>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

src/plugins/discover/public/application/view_components/canvas/top_nav.tsx

@@ -90,7 +90,7 @@ export const TopNav = ({ opts }: TopNavProps) => {
       showSaveQuery
       useDefaultBehaviors
       setMenuMountPoint={opts.setHeaderActionMenu}
-      indexPatterns={indexPatterns}
+      indexPatterns={indexPattern ? [indexPattern] : indexPatterns}
     />
   );
 };