docs: add docker/model-runner to CLI reference repos (#23536)

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## Description

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Add https://github.com/docker/model-runner to CLI reference repos.

## Related issues or tickets

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## Reviews

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- [ ] Technical review
- [ ] Editorial review
- [ ] Product review

Signed-off-by: Dorin Geman <[email protected]>

Author: doringeman

CONTRIBUTING.md

@@ -115,6 +115,7 @@ update the CLI reference docs, refer to the corresponding repository:
 - [docker/cli](https://github.com/docker/cli)
 - [docker/buildx](https://github.com/docker/buildx)
 - [docker/compose](https://github.com/docker/compose)
+- [docker/model-runner](https://github.com/docker/model-runner)
 
 Feel free to raise an issue on this repository if you're not sure how to
 proceed, and we'll help out.