`SearchHistory` internally enforced the max length of the search history
by popping elements from the front using `.remove(0)`. For a `Vec` this
is a `O(n)` operation. Use a `VecDeque` to make this `O(1)`

I also made it so the excess element is popped before the new one is
added, which keeps the allocation at the desired size.

Release Notes:

- N/A