[RFC] Migrate Nvidia CI from Modal to HF Jobs

### 🚀 The feature, motivation and pitch

Since a suitable sponsor for Nvidia CI is yet to be found, perhaps the CI could be migrated towards [HF Jobs](https://huggingface.co/docs/hub/jobs-overview), which provide Nvidia based container images and [usage-based pricing](https://huggingface.co/docs/hub/jobs-pricing). Here is an article which talks about migrating [CI to HF Jobs](https://huggingface.co/blog/github-ci-hf-jobs) with a YAML based configuration like Github.

### Alternatives

_No response_

### Additional context

I'm not affiliated with HF, I believe that having developer confidence while contributing to this great project can be done with a stable CI/CD, so I considered HF Jobs to be a suitable alternative.

The issue names no files, tests, or current CI entry point; begin by locating the Nvidia CI and Modal configuration in Liger-Kernel and reviewing the linked HF Jobs documentation. Done would require an agreed migration design and stable Nvidia CI/CD execution, but the issue does not define implementation or validation details.

Written by the indexing model from the issue text.