docs/data/reusables/github-actions/self-hosted-runner-labels-runs-on.md

To specify a self-hosted runner for your job, configure runs-on in your workflow file with self-hosted runner labels.

All self-hosted runners have the self-hosted label. Using only this label will select any self-hosted runner. To select runners that meet certain criteria, such as operating system or architecture, provide an array of labels that begins with self-hosted (this must be listed first) and then includes additional labels as needed.