[SPARK-53592][PYTHON][TESTS][FOLLOW-UP] Remove unused config in the parity test

### What changes were proposed in this pull request?
Remove unused config in the parity test

### Why are the changes needed?
this config is not used

### Does this PR introduce _any_ user-facing change?
no, test-only

### How was this patch tested?
ci

### Was this patch authored or co-authored using generative AI tooling?
no

Closes #52403 from zhengruifeng/udf_test_followup.

Authored-by: Ruifeng Zheng <[email protected]>
Signed-off-by: Ruifeng Zheng <[email protected]>

Author: zhengruifeng

python/pyspark/sql/tests/connect/test_parity_unified_udf.py

@@ -22,10 +22,7 @@
 
 
 class UnifiedUDFParityTests(UnifiedUDFTestsMixin, ReusedConnectTestCase):
-    @classmethod
-    def setUpClass(cls):
-        ReusedConnectTestCase.setUpClass()
-        cls.spark.conf.set("spark.sql.execution.pythonUDF.arrow.enabled", "false")
+    pass
 
 
 if __name__ == "__main__":