### What changes were proposed in this pull request?
Update `ObjectSerializerPruning.alignNullTypeInIf`, to consider the isNull check generated in `RowEncoder`, which is `Invoke(inputObject, "isNullAt", BooleanType, Literal(index) :: Nil)`.
### Why are the changes needed?
Query fails if we don't fix this bug, due to type mismatch in `If`.
### Does this PR introduce _any_ user-facing change?
Yes, the failed query can run after this fix.
### How was this patch tested?
new tests
Closes#29467 from cloud-fan/bug.
Authored-by: Wenchen Fan <wenchen@databricks.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
f33b64a656