[Nemo Unit Tests] Split CPU unit tests
![image](https://github.com/user-attachments/assets/c1ed7e2e-3bfd-4489-889d-8a657ca6a1a9)

CI passed

> Can we make the the unit tests required?

done CI passed https://github.com/NVIDIA/NeMo/actions/runs/10732427046/job/29771216029?pr=10365
Split CPU unit tests