Integrate output differ with nightly build

[rousik]

The goal of this feature is to develop output differ tool that can compare two outputs and generate human-friendly actionable reports that can help people diagnose the cause of data discrepancies.

This consists of the following sub-tasks:

• [ ] develop usable output differ prototype that can compare outputs (perhaps even partially)
• [ ] run output differ via github actions
• [ ] trigger github actions as part of the nightly build process
• [ ] Stretch goal: trigger github action as part of PR into dev branch for early detection on etl_fast.yml