idToken returns null always for Discord

## Issue
While using discord as a provider, `idToken` is always null. My implementation:
```
const config = {
issuer: "https://discord.com",
clientId:
clientSecret: ,
redirectUrl: ,
scopes: ["email", "identify"],
serviceConfiguration: {
authorizationEndpoint: "https://discord.com/oauth2/authorize",
tokenEndpoint: "https://discord.com/api/oauth2/token",
},
}

const authResult = await authorize(config)
```

This is the response that I get when calling `authorize`
```
{"accessToken": , "accessTokenExpirationDate": "2023-07-06T20:20:23Z", "authorizeAdditionalParameters": {}, "idToken": null, "refreshToken": , "scopes": [], "tokenAdditionalParameters": {}, "tokenType": "Bearer"}
```

---

## Environment

* **Your Identity Provider**: `Discord`
* **Platform that you're experiencing the issue on**: `both`
* **Are you using Expo?** No