Fix type error while indexing DestinationTag

[pkcs8]

[pkcs8]

With index template mapping enabled, platform-server prints this in log:

2023-11-24T03:19:56+05:30 TRC Bulk index error hash=2E67103E0E55F67CFA035161F123FCE63D9ED643D2BCB05A28DC0FACDE9AA5CA reason="[1:165] failed to parse field [DestinationTag] of type [integer] in document with id '2E67103E0E55F67CFA035161F123FCE63D9ED643D2BCB05A28DC0FACDE9AA5CA'. Preview of field's value: '2807917334'" type=document_parsing_exception

DestinationTag should be converted to int32 before sending for indexing.