Update python/docs/source/migration_guide/pyspark_upgrade.rst

Co-authored-by: Allison Wang <allison.wang@databricks.com>

Author: HyukjinKwon

python/docs/source/migration_guide/pyspark_upgrade.rst

@@ -24,7 +24,7 @@ Upgrading from PySpark 4.0 to 4.1
 
 * In Spark 4.1, Arrow-optimized Python UDF supports UDT input / output instead of falling back to the regular UDF. To restore the legacy behavior, set ``spark.sql.execution.pythonUDF.arrow.legacy.fallbackOnUDT`` to ``true``.
 
-* In Spark 4.1, unnecessary conversion to pandas instances is removed when ``spark.sql.execution.pythonUDTF.arrow.enabled`` is enabled. As a result, the type coercion changes when the produced output has a schema different from the specified schema. To restore the previous behavior, ``enable spark.sql.legacy.execution.pythonUDTF.pandas.conversion.enabled``.
+* In Spark 4.1, unnecessary conversion to pandas instances is removed when ``spark.sql.execution.pythonUDTF.arrow.enabled`` is enabled. As a result, the type coercion changes when the produced output has a schema different from the specified schema. To restore the previous behavior, enable ``spark.sql.legacy.execution.pythonUDTF.pandas.conversion.enabled``.
 
 
 Upgrading from PySpark 3.5 to 4.0