Livedata table headers buttons should not be read out

When working on a solution for XWIKI-20755, some tests were conducted.
https://up1.xwikisas.com/#l1XOVVUqfjwiy-KFPsZfTg
Here we could see that the header for live data tables is read out with both buttons, and not just the actual table header:
"Drag to reorderPage Drag to resize. Double click to reset." instead of "Page".
This creates a lot of clutter when navigating in the table with assistive technologies.
Both control elements reference drag actions, which are inherently not accessible. Those elements should not appear to assistive technology users.