CDB3-3272 Cancelation procedure

Steps to reproduce:

1. Create procedure
2. Cancel procedure with "reason": {"uk_UA": "Якась причина скасування аукціону"}

Actual result:
https://procedure-dev.prozorro.sale/api/procedures/6335237136db6f918b5df0c8

Expected result:
Reason should have be from list [1:5]
e.g - "reason": {"uk_UA": "2"}
https://procedure-dev.prozorro.sale/api/dictionaries/smallPrivatizationCancellationReason