feat: Support Electron

[timfish]

• Closes Add support for Electron built output paths #6

This PR:

• Uses the @electron/rebuild output path to load the profiling binary if we're running in Electron
  • Logs a warning on error instructing users to use @electron/rebuild when using Electron
• Adds tests for Electron
• The bundler tests still pass!
• Splits the tests into bindings/bundling/electron
  • Only runs the required tests on all platforms and Node versions
  • Keeps all the test dependencies contained within their own tests to keep yarn install times reasonable on Windows