[@nativescript/google-signin] Tethered Device SignIn

[NicholasSmilovic]

Not really a bug but didn't know the etiquette to share for other people who encounter this issue.

Calling GoogleSignin.signIn on a tethered device results in an error of Error: |presentingViewController| must be set.

Traced this to index.ios.js const keyWindow = UIApplication.sharedApplication.keyWindow; is null since I'm guessing my keyWindow actually is related to my physical keyboard.

Switched to an emulator and everything is fine.