Bug 32891: Fix slot selection in last hour

Bug 32891: Fix slot selection in last hour

If the curbside pickup module is configured with slot not on the hour
(minutes=00), the slots in the last (not complete) hour won't be
selectable.

Test plan:
Create the following configuration:
pickup interval: 10
Opening hours: 08:00 to 11:30
Create a pickup and select 11:10 or 11:20
=> Without this patch the pickup is not created and the UI displays "Wrong slot selected"
=> With this patch you are able to create the pickup

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Caroline Cyr La Rose <caroline.cyr-la-rose@inlibro.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>