bump actions/checkout to v4

[yassinebenaid]

This PR bumps the actions/checkout from v3 to v4.

Issue warned on actions tab

The following actions uses Node.js version which is deprecated and will be forced to run on node20: actions/checkout@v3. For more info: https://github.blog/changelog/2024-03-07-github-actions-all-actions-will-run-on-node20-instead-of-node16-by-default/

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