remove warning filter for datetime.datetime.utcfromtimestamp

[kevinjqliu]

Apache Iceberg version

None

Please describe the bug 🐞

datetime.datetime.utcfromtimestamp is deprecated starting from 3.12
https://docs.python.org/3.12/library/datetime.html#datetime.datetime.utcfromtimestamp

Pyspark still use datetime.datetime.utcfromtimestamp, which was recently changed apache/spark@8e02a64#diff-bb02965370d515ec7add7967bc949c18c88ffc7346cceaebefb84907dfdce903L437 and will be available in version 4.0

Need to keep the warning filter until pyspark 4.0