We should remove the internal `_usePrometheusPoll` hook from the public API. This API was introduced in 4.11, so we can remove it before GA without making an API breaking change. Making this a high severity bug since we don't want to accidentally ship it in 4.11 GA, after which we have to deprecate before we can remove.
NOTE: We should ONLY remove the hook that starts with the underscore. `usePrometheusPoll` without an underscore is an API we want to keep.
*** This bug has been marked as a duplicate of bug 2093047 ***
I'll address this part of my PR for the other bug (2093047).