[BUG] Writing Parquet map(map) column can not set the outer key as non-null.

[res-life]

Describe the bug
Reports the following error when writing map(map) column.

key column can not be nullable

The SchemaUtils.writerOptionsFromField can not handle map(map) column.
SchemaUtils uses structBuilder to simulate mapBuilder, but does not set the outer key as non-null. For the inner key, it's OK.

Steps/Code to reproduce bug

val data = Seq(
  (Map(Map(111->111, 112->112) -> 1, Map(121->121, 122->122) -> 2), 1),
  (Map(Map(211->111, 212->112) -> 1, Map(221->121, 222->122) -> 2), 2)
)
val df = spark.createDataFrame(data).toDF("c1", "c2")
df.write.parquet("/tmp/a.parquet")

Error:

Caused by: org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 0.0 failed 1 times, most recent failure: Lost task 0.0 in stage 0.0 (TID 0) (chongg-pc executor driver): java.lang.IllegalArgumentException: key column can not be nullable
	at ai.rapids.cudf.ColumnWriterOptions.mapColumn(ColumnWriterOptions.java:530)
	at com.nvidia.spark.rapids.SchemaUtils$.writerOptionsFromField(SchemaUtils.scala:298)
	at com.nvidia.spark.rapids.SchemaUtils$.$anonfun$writerOptionsFromSchema$1(SchemaUtils.scala:329)
	at scala.collection.Iterator.foreach(Iterator.scala:943)
	at scala.collection.Iterator.foreach$(Iterator.scala:943)
	at scala.collection.AbstractIterator.foreach(Iterator.scala:1431)
	at scala.collection.IterableLike.foreach(IterableLike.scala:74)
	at scala.collection.IterableLike.foreach$(IterableLike.scala:73)
	at org.apache.spark.sql.types.StructType.foreach(StructType.scala:102)
	at com.nvidia.spark.rapids.SchemaUtils$.writerOptionsFromSchema(SchemaUtils.scala:327)
	at com.nvidia.spark.rapids.GpuParquetWriter.<init>(GpuParquetFileFormat.scala:374)
	at com.nvidia.spark.rapids.GpuParquetFileFormat$$anon$1.newInstance(GpuParquetFileFormat.scala:287)
	at org.apache.spark.sql.rapids.GpuSingleDirectoryDataWriter.newOutputWriter(GpuFileFormatDataWriter.scala:235)
	at org.apache.spark.sql.rapids.GpuSingleDirectoryDataWriter.<init>(GpuFileFormatDataWriter.scala:217)
	at org.apache.spark.sql.rapids.GpuFileFormatWriter$.executeTask(GpuFileFormatWriter.scala:326)
	at org.apache.spark.sql.rapids.GpuFileFormatWriter$.$anonfun$write$15(GpuFileFormatWriter.scala:266)
	at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:90)
	at org.apache.spark.scheduler.Task.run(Task.scala:136)
	at org.apache.spark.executor.Executor$TaskRunner.$anonfun$run$3(Executor.scala:548)
	at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1504)
	at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:551)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:750)

Environment details (please complete the following information)
Branch 23.10

[sameerz]

Related to rapidsai/cudf#14003