Forward fix test_create_submodule_list_return to be backwards compatible (#591)

Summary:
Pull Request resolved: https://github.com/pytorch/executorch/pull/591

From `TODO` comment:

`split.Tensor` now gets decomposed to split_with_sizes. Due to how executorch uses a pinned Pytorch nightly, the CI may not catch the changes to Pytorch's core decomposition table. As a temporary workaround, make the test backwards compatible with the old decomposition table. Remove the or statement once Pytorch nightly has been updated.

Reviewed By: dbort

Differential Revision:
D49878902

Privacy Context Container: L1124100

fbshipit-source-id: f2ab4a035aa7e0dd3208b6352432a7afe4f255d9