Bug 24410: Fix multi holds

Bug 24410: Fix multi holds

Bug 19618 replaces the call to placerequest.pl with a REST API /holds
That is wrong as it does not support multi holds.

Test plan:
Confirm that prior to this patch you are not able to place a hold on
several records at once, and that this patch fixes it

Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Agustin Moyano <agustinmoyano@theke.io>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Joy Nelson <joy@bywatersolutions.com>