Serialized messages contains BackingField with duplicated data

[denis-tsv]

PROPERTY_k__BackingField values can be removed, they contains duplicated data

Serialized message example
{
"MeetingGroupProposalId": "674e153e-a1bf-40ce-aa2e-139bf37cd39a",
"Name": "test",
"Description": "test",
"LocationCity": "test",
"LocationCountryCode": "tst",
"ProposalUserId": "4065630e-4a4c-4f01-9142-0bacf6b8c64d",
"ProposalDate": "2020-03-11T01:08:06.1942544Z",
"Id": "d2757a04-e929-4ccf-a23b-360abe1f5b93",
"OccurredOn": "2020-03-11T01:08:15.1182219Z",
"<MeetingGroupProposalId>k__BackingField": "674e153e-a1bf-40ce-aa2e-139bf37cd39a",
"<Name>k__BackingField": "test",
"<Description>k__BackingField": "test",
"<LocationCity>k__BackingField": "test",
"<LocationCountryCode>k__BackingField": "tst",
"<ProposalUserId>k__BackingField": "4065630e-4a4c-4f01-9142-0bacf6b8c64d",
"<ProposalDate>k__BackingField": "2020-03-11T01:08:06.1942544Z"
}

[kgrzybek]

Resolved, thanks for the issue!