Interpret Parquet INT96 type as FIXED[12] AVRO Schema

Reading Parquet files in Apache Beam using ParquetIO uses `AvroParquetReader` causing it to throw `IllegalArgumentException("INT96 not implemented and is deprecated")`

Customers have large datasets which can't be reprocessed again to convert into a supported type. An easier approach would be to convert into a byte array of 12 bytes, that can then be interpreted by the developer in any way they want to interpret it.