This PR updates the build script:
* fixed issue where program version check was not properly triggering;
* improved `git-clean` command to correctly clear Scala artifacts;
* added `run.ps1` wrapper to the build script that works better with PowerShell than `run.cmd`;
* increased timeouts to work around failures on macOS nightly builds;
* replaced depracated GitHub Actions APIs (set-output) with their new equivalents;
* workaround for issue with electron builder (python2 lookup) on newer macOS runner images;
* GUI and backend dispatches to cloud were completed;
* release workflow allows creating RC releases.
