[MAINTAIN] Refactor step.py

[AsadJeewa]

Please describe what needs to be maintained.

step.py has too many components, some of which are independent i.e. Step and TrainerStep both extend Component

Describe the outcome you'd like

Improved readability of step.py by renaming variables or separating them into files

How do we know when maintenance is complete?

Checklist:

• [ ] Refactor PR merged into dev