Add is_distributed to Strategy API and remove accl_conn is_distributed property

[four4fish]

What does this PR do?

Fixes #11449 TODO item, remove unused properties

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[ananthsub]

It seems like the only place inside of Lightning that needs this property is the data connector. I feel #11756 is a better solution for handling the distributed sampler compared to requiring every property to declare whether it's distributed or not

[four4fish]

It seems like the only place inside of Lightning that needs this property is the data connector. I feel #11756 is a better solution for handling the distributed sampler compared to requiring every property to declare whether it's distributed or not

@ananthsub LightningLite is depending on this as well

[ananthsub]

@ananthsub LightningLite is depending on this as well

Lite relies on it for setting up dataloaders, which is exactly why this logic should be put into the strategy. it's still the same feature request. Lite can directly depend on the strategy for process_dataloader.

[four4fish]

@ananthsub LightningLite is depending on this as well

Lite relies on it for setting up dataloaders, which is exactly why this logic should be put into the strategy. it's still the same feature request. Lite can directly depend on the strategy for process_dataloader.

Oh I see! That make sense, will abandon this PR then. Let's do the #11756 way