update link to PL docs (#3237)

update link to PL docs talking about DeepSpeed integration

README.md

@@ -96,7 +96,7 @@ DeepSpeed has been integrated with several different popular open-source DL fram
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 <img src="docs/assets/images/transformers-light.png#gh-light-mode-only" width="250px"><img src="docs/assets/images/transformers-dark.png#gh-dark-mode-only" width="250px"> | [Transformers with DeepSpeed](https://huggingface.co/docs/transformers/main/main_classes/deepspeed) |
 | <img src="docs/assets/images/accelerate-light.png#gh-light-mode-only" width="250px"><img src="docs/assets/images/accelerate-dark.png#gh-dark-mode-only" width="250px"> | [Accelerate with DeepSpeed](https://huggingface.co/docs/accelerate/usage_guides/deepspeed) |
-| <img src="docs/assets/images/lightning-light.svg#gh-light-mode-only" width="200px"><img src="docs/assets/images/lightning-dark.svg#gh-dark-mode-only" width="200px"> | [Lightning with DeepSpeed](https://pytorch-lightning.readthedocs.io/en/stable/api/pytorch_lightning.strategies.DeepSpeedStrategy.html) |
+| <img src="docs/assets/images/lightning-light.svg#gh-light-mode-only" width="200px"><img src="docs/assets/images/lightning-dark.svg#gh-dark-mode-only" width="200px"> | [Lightning with DeepSpeed](https://lightning.ai/docs/pytorch/stable/advanced/model_parallel.html#deepspeed) |
 | <img src="docs/assets/images/mosaicml.svg" width="200px"> | [MosaicML with DeepSpeed](https://docs.mosaicml.com/en/latest/trainer/using_the_trainer.html?highlight=deepspeed#deepspeed-integration) |
 | <img src="docs/assets/images/determined.svg" width="225px"> | [Determined with DeepSpeed](https://docs.determined.ai/latest/training/apis-howto/deepspeed/overview.html) |