FailOnAllUnknownTypesExceptNull

Intended for Avro and Parquet Conversions and similar use cases.

The contract is to serialize the values of schemaless and unknown types to a json string.

Because there is no JsonBlob AirbyteType, we leave the types as-is and just serialize them. It is expected that the serializer will know to expect strings for each type.

This means there's no need for a type mapper, unless you also want to support some subset of the Unknown types.

For example, FailOnAllUnknownTypesExceptNull is used to add support for { "type": "null" }