fix asr finetune
# What does this PR do ?

Fix the bug that `model.hparams` were not updated when changes to `model._cfg` were made directly (e.g., in `model.setup_optimization()`)


**Collection**: [asr,core]


**PR Type**:
- [ ] New Feature
- [x] Bugfix
- [ ] Documentation


# Additional Information
* Related to https://github.com/NVIDIA/NeMo/issues/9824
