[Refactor] Dreamer v1 refactor

[MateuszGuzek]

Description

Draft PR to facilitate discussion:

The proposed change extracts training steps in wrappers to reduce length of the example, but as there few control logging parameters needed, it creates nasty large function signatures, which are split multi-line by µfmt and do not really achieve the goal IMHO. (If such change would be accepted, the wrappers can be clearly moved to utils or models file.)

@vmoens @BY571

Motivation and Context

Discuss ideas for refactoring Dreamer V1.

Types of changes

Refactor

Checklist

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• [ ] I have read the CONTRIBUTION guide (required)
• [ ] My change requires a change to the documentation.
• [ ] I have updated the tests accordingly (required for a bug fix or a new feature).
• [ ] I have updated the documentation accordingly.