[Feature Request] Allowing to customize group keyword in column header when Grouping Rows In Datatable

Problem to solve

Instead of text, I want to add an Icon, without overriding the entire header slot & re-writing the sort and other column logic.

Proposed solution

The Expand Group/Collapse Group Icons in table body & Group keyword in column header should be customizable allowing text and icons, to be changed. Currently, there are slots for group header & summary but, I want to just change a few labels. Maintaining the default functionality