ParquetTimestampAttribute has no effect on nullable DateTime properties

[aden-74]

The documentation says that to use non-legacy date type, we need to annotate a property with [ParquetTimestamp]:

[ParquetTimestamp]
public DateTime TimestampDate { get; set; }

Yes, this works. But it does not work when you use nullable DateTime, like the following:

[ParquetTimestamp]
public DateTime? TimestampDate { get; set; }

In this case, dates are serialized as INT96 numbers.

[aloneguid]

This is fixed in 4.23.0, please feel free to validate and re-open if any issues.