chore: fix sync repository action (bis)

[RomanBredehoft]

it's still failing : https://github.com/zama-ai/concrete-ml/actions/runs/8522402034/job/23342541783

the issue is that the external action does not provide any LFS options

also, it looks like we were cloning the repo twice, so I remove the external action and simplified to these steps

[jfrery]

You can test the workflow on this branch maybe first so that you don't have to merge to main to see if it works.

Just comment

    branches:
      - 'main'

[RomanBredehoft]

I'm usually not a fan of doing this when we are doing things related to main, but in this case I think it should be good indeed, will do thanks !

[RomanBredehoft]

I can't find a way to make this work, it's pretty weird

[jfrery]

Thanks for fixing this!

[RomanBredehoft]

finally working 🎉