Verify GHCR write access

Workflow runs for Verify GHCR write access

• ci: resolve the GHCR-provided cancellation endpoint

  failed:
  Verify GHCR write access#3:Commitb95e55cpushedbyGCWing
  gcwing/verify-ghcr-write-access

  Nov 14, 20266s
  More actions for workflow run 3

• ci: accept same-registry upload cancellation locations

  failed:
  Verify GHCR write access#2:Commit832017apushedbyGCWing
  gcwing/verify-ghcr-write-access

  Nov 14, 20265s
  More actions for workflow run 2

• ci: verify GHCR write access without uploading an image

  failed:
  Verify GHCR write access#1:Commit10d0ab2pushedbyGCWing
  gcwing/verify-ghcr-write-access

  Nov 14, 20265s
  More actions for workflow run 1