Bug 36775: Allow multiple holds on record when holds per record is unlimited

Bug 36775: Allow multiple holds on record when holds per record is unlimited

To test:
1 set Holds Per Record to Unlimited
2 confirm hold placement interface does not include "Holds to place (count)"
3 apply patch, restart all
4 reload hold placement interface, confirm it does include "Holds to place (count)"
5 set Holds Per Record to 2
6 confirm Holds to place shows when placing a first hold for a patron, but not when placing a second
7 set Holds Per Record to 1
8 confirm Holds to Place does not show
9 sign off and eat a nice snack

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Emily Lamancusa <emily.lamancusa@montgomerycountymd.gov>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>