Add custom dataloader support with Lite

[tchaton]

What does this PR do?

This PR enables the following Custom DataLoader not to crash.

This would work

class CustomDataLoader(DataLoader):
    def __init__(self, value: int, *args, **kwargs):
        super().__init__(range(value), *args, **kwargs)

class LiteWithCustomDataLoader(LightningLite):
    def run(self):
        # This doesn't fail as the context manager would save all the arguments provided
        # to the dataloaders.
        dataloader = CustomDataLoader(2, batch_size=2)
        self.setup_dataloaders(dataloader)

LiteWithCustomDataLoader().run()

Would we failed as the value has been captured.

dataloader = CustomDataLoader(2, batch_size=2)
lite_dataloader = lite.setup_dataloaders(dataloader)

This would enable to remove this ugliness from PyTorch Geometric: https://github.com/pyg-team/pytorch_geometric/blob/master/torch_geometric/loader/dataloader.py#L74 if they use LightningLite.

This would be added to Lightning in another PR.

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

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[github-actions]

Build Error! No Linked Issue found. Please link an issue or mention it in the body using #<issue_id>

[github-actions]

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[ethanwharris]

LGTM, small comment

[kaushikb11]

LGTM!

[carmocca]

cc @awaelchli

[carmocca]

Won't this get possibly overridden by the __dict__.update above?

[awaelchli]

the __* methods don't get affected by direct update to __dict__

[awaelchli]

@carmocca We can accumulate these smaller things like typing in #10297 and make separate PRs where needed as discussed in #10329