Implement Spark-compatible CAST to/from TimestampNTZType

[andygrove]

What is the problem the feature request solves?

TimestampNTZType casts are not currently tested in CometCastSuite because this type is not available in all supported Spark versions and we don't have 3.x minor version shims in place yet.

This issue is for adding the shims and tests for casts to/from this type.

Describe the potential solution

No response

Additional context

No response

[parthchandra]

There is support for some casts involving timestamp and timestamp_ntz - https://github.com/apache/datafusion-comet/blob/b39ed8823a6bf5ce7b624918c37cec40afcf7b36/spark/src/test/scala/org/apache/comet/CometExpressionSuite.scala#L261