The runner has received a shutdown signal. This can happen when the runner service is stopped, or a manually started runner is canceled.

Process completed with exit code 137.

Executing in debug mode!

The debug output will be written but no issues/PRs will be processed.

No more operations left! Exiting...

If you think that not enough issues were processed you could try to increase the quantity related to the operations-per-run (​https://github.com/actions/stale#operations-per-run​) option which is currently set to 30