[Feat] Add Loops Restart

[tchaton]

What does this PR do?

Fixes #8126.

TODOS:
[x] Add restart for training epoch loop
[x] Add restart for training batch loop
[x] Add restart for multiple optimizers
[x] Add support random samplers
[x] Add support accumulate_grad_batches (saving gradients)
[x] Add checkpoint creation on failure
[x] Add mechanism to prevent DDP deadlock on failure: Merged #8167
[x] Add restart for validation epoch loop
[x] Add restart for the validation batch loop
[x] Add restart for multiple validation dataloaders
[x] Add val_check_internval
[x] Add FastForwardSampler and CaptureIterativeDataset to recover dataset states. # #8307
[] Add support for results / extras on epoch_end for train
[] Add restore / restarting attribute function to Loops
[] Link progress tracking to Loop attributes
[] Investigate InfiniBatch for random seed (num_workers, ddp sampler)
[] Handle manual optimizer step (optimizer step / zero grad to take care of)
[] Test DistributedSampler
[] Add configuration mechanism to restart as currently supported. Start from next epoch.
[] Restart validation loop using should_check_val.

Before submitting

• Was this discussed/approved via a GitHub issue? (not for typos and docs)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure your PR does only one thing, instead of bundling different changes together?
• Did you make sure to update the documentation with your changes? (if necessary)
• Did you write any new necessary tests? (not for typos and docs)
• Did you verify new and existing tests pass locally with your changes?
• Did you update the CHANGELOG? (not for typos, docs, test updates, or internal minor changes/refactorings)

PR review

Anyone in the community is free to review the PR once the tests have passed.
Before you start reviewing make sure you have read Review guidelines. In short, see the following bullet-list:

• Is this pull request ready for review? (if not, please submit in draft mode)
• Check that all items from Before submitting are resolved
• Make sure the title is self-explanatory and the description concisely explains the PR
• Add labels and milestones (and optionally projects) to the PR so it can be classified

Did you have fun?

Make sure you had fun coding 🙃

[tchaton]

This PR is closed in favour of #8337