Push action failed with empty list during Github actions outage

[lexton]

During the Github actions outage this morning - we were seeing push type action with a base commit that was loaded incorrectly as a null commit - formatted as a string of zero's rather than null or the empty string.

Base commit: 0000000000000000000000000000000000000000

Info level logs:

...
2022-03-16T19:42:47.8550564Z ##[group]Run jitterbit/get-changed-files@v1
2022-03-16T19:42:47.8550984Z with:
2022-03-16T19:42:47.8551518Z   token: ***
2022-03-16T19:42:47.8551883Z   format: space-delimited
2022-03-16T19:42:47.8552240Z env:
2022-03-16T19:42:47.8552845Z   TERM: xterm
2022-03-16T19:42:47.8553209Z   AWS_REGION: us-east-1
2022-03-16T19:42:47.8553576Z   name: DEST::/home/runner/bin
2022-03-16T19:42:47.8553941Z   PR_NUMBER: 5117
2022-03-16T19:42:47.8554324Z   BASE_REF: <REDACTED>
2022-03-16T19:42:47.8554738Z ##[endgroup]
2022-03-16T19:42:47.9280476Z Base commit: 0000000000000000000000000000000000000000
2022-03-16T19:42:47.9281842Z Head commit: <REDACTED>
...

This caused the changed files to be returned as empty, and the lookup to have succeeded.

Expected error

The base and head commits are missing from the payload for this push event. Please submit an issue on this action's GitHub repo.

Expected Mitigation

No needed mitigation, as Github service returned the issue went away.

[lexton]

I believe this manifests very similarly to: #10