Create sandbox job and run it on a schedule

[bcipriano]

Is your feature request related to a problem? Please describe. Sometimes upstream dependencies change without us noticing and break documented process, such as the sandbox. For example, #1101.

Describe the solution you'd like Create a Github Action to test the sandbox setup process -- on Linux and macOS if possible. This job should run daily, or maybe every few days.

Describe alternatives you've considered We could use some sort of CI system for this as well, if Github Actions doesn't do what we need.