Parquet column array<struct<>> with null value is read in as empty list #251

Apache Iceberg version

main (development)

Please describe the bug 🐞

An Iceberg table with column type array that has null value is read in as empty list, however, it should be none instead.

reproducible scripts: puchengy@3fd6d3d

shows

>       assert pyberg_val == direct_val
E       assert [] == None