Update on "[ExecuTorch][#10447] Extend PyBundledModule with extension.BundledModule"

# Context

This issue is a step of #9638.

In #9638, we want to have `extension.Module` as the single source of implementation in `pybindings`, which means that `pybindings.PyModule` should use `extension.Module` rather than its own `pybindings.Module`.

# Proposal

Now that we have `extension.BundledModule` ready, we want to test it out by having our existing `PyBundledModule` to extend it, and let `verify_result_with_bundled_expected_output` to use it, so that we can test out the whole thing with https://github.com/pytorch/executorch/blob/fb45e19055a92d2a91a4d4b7008e135232cbb14b/devtools/bundled_program/test/test_end2end.py

Differential Revision: [D73564127](https://our.internmc.facebook.com/intern/diff/D73564127/)

[ghstack-poisoned]

Author: Gasoonjia