chore(TreeList): remove invalid link

Currently, we do not expose the OnRead event for the TreeList, so the suggested approach in the KB article is invalid.

Author: Tsvetomir-Hr

knowledge-base/grid-search-button-click.md

@@ -137,6 +137,5 @@ Also see the [Filter Descriptors documentation]({%slug components/grid/filtering
 ## See Also
 
 * [Search the Grid in Numeric and Date Model Fields]({%slug grid-kb-search-numeric-fields%})
-* [Search the Grid in Hidden Fields]({%slug grid-kb-search-in-hidden-fields%})
 * [Search the Grid with a `StartsWith` operator]({%slug grid-kb-search-startswith%})
 * [Format or Bold Search Results in the Grid]({%slug grid-kb-search-highlight-results%})