Added Universal binary option for macOS

[arunavo4]

@saltyshiomix The --universal flag was missing for the macOS . I added the flag for people who wants to create the macOS Universal binary.

[andirsun]

I dont see the --universal option on electron builder CLI options, can you point me out to the code? https://www.electron.build/cli

Nevermind I found it. https://github.com/electron-userland/electron-builder/issues/5689#issuecomment-792876001

[andirsun]

@m5x5 please review this.

[saltyshiomix]

@arunavo4 CC: @andirsun @milanmdev Nextron v8.2.0 is out which includes your PR 🎉