3/n Consolidate collective functions - Integrate with TrainingTypePlugin

[four4fish]

What does this PR do?

Implementing proposal here https://docs.google.com/document/d/1e83FcZHHHsTmiUmNpgmPTBYjugZaC3pcZhd4VV9AuIM/edit

Steps:

1. [RFC] create pytorch_lightning/utilities/collective_util.py and move collective related utils from distributed.py to collective_util.py
2. 2/n Consolidate collective functions - collective base and subclasses. (this PR)
3. Integrate with all training_type_plugins (ddp, dp, fullshard and etc) and
4. Integrate with Accelerators

Fixes #7534

Does your PR introduce any breaking changes? If yes, please list them.

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[stale]

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[tchaton]

Hey @four4fish,

What is the status on this PR ?

Best,
T.C

[four4fish]

@tchaton this is pending on 2/n Consolidate collective functions - collective base and subclasses #9414. There are some open questions about the api design still in discussion
Collective refactor will not be included in 1.5 release.

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