v6 doesn't name artifacts correctly for Windows nupgk

[ahallicks]

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• I have searched the issue tracker for an issue that matches the one I want to file, without success.

Please describe your issue:
When I run npm run publish it creates a nupkg file and the setup.exe. My version is set to 3.0.0-beta.3.

The setup file has this exact version (AppName-3.0.0-beta.3-Setup.exe) but the nupgk file is AppName-3.0.0-beta3-full.nupkg.

Notice the missing . in the beta bit. It then can't upload the assets as it's looking for a file with the name AppName-3.0.0-beta.3-full.nupkg.

Console output when you run electron-forge with the environment variable DEBUG=electron-forge:*. (Instructions on how to do so here). Please include the stack trace if one exists.

I'll do this when I'm back at my computer! 

What command line arguments are you passing?

Just

npm run package

What does your config.forge data in package.json look like?

IOU one config 

Please provide either a failing minimal testcase (with a link to the code) or detailed steps to
reproduce your problem. Using electron-forge init is a good starting point, if that is not the
source of your problem.

Seems to specifically be for beta where that extra . isn't added to the name so any simple app will fail in the same way.