[Misc] Gemma3ForConditionalGeneration supports LoRA

[jeejeelee]

FIX #14789

[github-actions]

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[DarkLight1337]

Can you merge from main to fix the CI?

[jeejeelee]

Can you merge from main to fix the CI?

Done

[DarkLight1337]

@WoosukKwon do you know whether this model is supposed to support LoRA already?

[WoosukKwon]

@DarkLight1337 Oh I don't see any reason not. While I haven't tested myself, I think the model should be able to support it.

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @jeejeelee.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork