[BUG] [AUDIT 4.0] Evaluate ordering fix in GpuCanonicalize::gatherCommutative

[mythrocks]

This concerns SPARK-50749, which fixed an expression-ordering problem introduced in https://issues.apache.org/jira/browse/SPARK-49977.

The Spark 4.0 refactors seem to have shuffled code around, to put the affected code in CommutativeExpression. The corresponding code in spark-rapids is in GpuCanonicalize.scala.

My reading of the code is that the expression order is correct in spark-rapids, per the recursive call. The Spark 4.0 version of the code replaces the recursion with an explicit queue/stack. If SPARK-49977 is introduced into spark-rapids, we'd also need to include SPARK-50759's fix.