Fix missing reject for init

[fehergeri13]

When I init the oneSignal sdk with some invalid config, I get the following error:

try {
    await OneSignal.init({ appId: "example app id" });
} catch(e) {
    console.log("error with init")
}

Uncaught (in promise) Error: OneSignalSDK: HTTP sites are no longer supported starting with version 16 (User Model), your public site must start with https://. Please visit the OneSignal dashboard's Settings > Web Configuration to find this option.

This is an example error. The main issue is that the error is uncaught.

This PR will fix the uncaught exception

[iAmWillShepherd]

Thanks for opening the PR. I'll forward this to the team so they can review 🙏🏽