add code owners

[ArthurZucker]

What does this PR do?

Adds code owner to make sure reviewers are pinged accordingly!

[HuggingFaceDocBuilderDev]

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[Rocketknight1]

Being lazy to lessen my workload, could we automatically generate the mapping of models to owners, or manually generate it once and then add a CI test to ensure that new model additions have a matching CODEOWNERS line? This would mean that dispatch would happen automatically, instead of me manually doing it every time

If you want, I can write a script to guess which category each model is, and then we can fix up that list afterwards

[ArthurZucker]

For new model the issue is that we need to know if it's a vision model, language model or audio model etc. I can do it if you prefer 😉

[Rocketknight1]

Yes, I know! But we could just add a CI test that raises an error if the model isn't in CODEOWNERS, and then the PR author knows they need to add a line to assign it to the right person. I can add some comments in the file to tell them who to assign it to (or you can do it!) WDYT?