CI: Add gptqmodel to the CI

[BenjaminBossan]

This issue is to track the TODO from this comment. Once optimum 1.24.0 and transformers 4.49.0 are released, we should enable gptqmodel in the CI (and remove auto-gptq).

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

[BenjaminBossan]

Not stale. New optimum and transformers releases are out, we should be good to proceed.

[Qubitium]

@BenjaminBossan Affirmative. To be clear, should we clear out all autogptq specific base code or just remove autogptq ci tests and replace with gptqmodel tests only?

[BenjaminBossan]

Let's go with the latter.