Update Build System

[srinjoym]

Currently we're using electron-forge for packaging GitHub Classroom Assistant. This package depends on electron-prebuilt-compile which has become out of date and has security issues.

There are three possible solutions:

1. Switch to a different packager like electron-build
2. Wait for v6 of ElectronForge to be released which eliminates the dependency on electron-prebuilt-compile. Progress is being tracked in this issue.
3. Create a custom packager so we're not dependent on other packages

[malept]

I would be happy to help you migrate to Forge v6! FWIW, creating a custom packager is probably not in your best interests, from a technical debt POV.