Bug 35357: Remove item from holds queue when it is checked out

Bug 35357: Remove item from holds queue when it is checked out

Test Plan:
1) Place a hold on an item
2) Build the holds queue
3) Check out the item to a different patron than the one
   targeted in the holds queue
4) Verify the holds queue viewer still shows that item and patron
5) Apply this patch
6) Repeat stepts 1 through 3
7) Verify the holds queue viewer no longer shows that patron and item!

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>