Forgejo versions before 15 didn't support workflow expansion, and "runs-on" was necessary in callers of reusable workflows. janware.com now runs Forgejo 15.x, and the requirement is gone, so remove the config option.
Quoting from https://forgejo.org/docs/latest/user/actions/reference/
runs-on is typically a required field. However, if a job defines jobs.<job_id>.uses in order to reference a reusable workflow, then it is optional. See jobs.<job_id>.uses for more information on this behaviour.
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It is recommended that jobs.<job_id>.runs-on is omitted when using uses, as this will allow Forgejo to perform workflow expansion. Workflow expansion results in the target workflow’s jobs appearing in the UI as separate jobs. This provides an easier to understand experience for accessing the logs of each job, and permits the jobs to run on separate runners with their own runs-on fields.
Signed-off-by: Jan Lindemann <jan@janware.com>
Jan Lindemann
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