[TODO] What if we need the index of FLATTEN-ing something that translates to a VARIANT?

[labs-infra-reader-backup]

See more context:

remorph/core/src/main/scala/com/databricks/labs/remorph/parsers/snowflake/rules/FlattenLateralViewToExplode.scala

Lines 45 to 50 in 661b684

	if (flattenOutputReferencedColumns.contains("index")) {
	// TODO: What if we need the `index` of FLATTEN-ing something that translates to a VARIANT?
	// VARIANT_EXPLODE outputs a POS column, we need to add a test case for that.
	SubqueryAlias(
	Lateral(TableFunction(PosExplode(input)), outer = outer, isView = true),
	id,