Fix race condition in processFuncRequestQueue

Fix race condition in processFuncRequestQueue

The issue here was that the element was only removed from the queue
after the func request was processed, but within that process, other
function could access the queue, so the queue could even be empty
when this function finally wanted to remove the item.

Fixes: #10406.
(cherry picked from commit dadec50a18d92d24d42e1ccf7474f07a2a66b5b4)