runners-privilegedescalation runners are decommissioned. Revert the
actionlint config back to empty labels and migrate renovate.yaml to
ubuntu-latest so actionlint passes and the workflow can still run.
Co-Authored-By: Paperclip <noreply@paperclip.ing>
Commit 8e51b01 removed this label from the actionlint config, but
renovate.yaml still uses runs-on: runners-privilegedescalation.
actionlint exits 1 when it sees an unknown runner label, breaking
PR Validation CI on org/pulls/72.
Co-Authored-By: Paperclip <noreply@paperclip.ing>
ARC runner scale set was recreated on 2026-03-19 with label
`runners-privilegedescalation` but all shared workflows still referenced
`local-ubuntu-latest`. This label mismatch caused startup_failure on
every Release workflow and queued CI jobs with no runner to pick them up.
Updates all 4 workflows and the actionlint config to match the current
ARC runner scale set label.
Closes#27