Update requirements_lightning.txt
Could you also please update **lightning** version here: https://github.com/NVIDIA/NeMo/blob/main/requirements/requirements_vllm.txt#L8

(It's a separate requirements file used for creating virtual environment for vLLM; for verification we're going to add a vLLM export test to Github Actions soon in https://github.com/NVIDIA/NeMo/pull/11543)
PTL to 2.5.0.post0 (used in 24.12 release)