[WIP] Specify recoverWithNulls in from_json

[andygrove]

cuDF now allows us to specify a recovery mode when parsing JSON. The default mode throws an exception when invalid JSON is encountered, and there is now a RECOVER_WITH_NULL option, which should return a null value for each invalid JSON row in a column.

This PR specifies this option in map_utils::from_json. However, this is not working as expected, and I am creating this PR for discussion purposes.

The included test fails with:

ai.rapids.cudf.CudfException: CUDF failure at:/home/andy/git/nvidia/spark-rapids-jni/src/main/cpp/src/map_utils.cu:146: JSON Parser encountered an invalid format at location 109
        at com.nvidia.spark.rapids.jni.MapUtils.extractRawMapFromJsonString(Native Method)
        at com.nvidia.spark.rapids.jni.MapUtils.extractRawMapFromJsonString(MapUtils.java:49)
        at com.nvidia.spark.rapids.jni.MapUtilsTest.testFromJsonInvalidRows(MapUtilsTest.java:97)

[andygrove]

This is no longer needed