`stickyHeader` for `DataTableSkeleton`

[Lucide]

DataTableSkeleton's styles are a bit too rigid compared to the actual DataTable:

• stickyHeader tables aren't supported
• The toolbar size is fixed
• The batchSelection header look can't be replicated (with the extra header checkbox space)

[metonym]

This is a design request best suited for https://github.com/carbon-design-system/carbon/issues