ClientId may be undefined when using FedCM login

[infinnie]

Describe the bug
When using FedCM sign-in in Google Chrome, the clientId field passed to the callback may be undefined.

To Reproduce
Steps to reproduce the behaviour:

1. Log in to Google Chrome
2. Open a page that calls useOneTap() method to display Google’s OneTap sign in UI.
3. When clicking Continue as [[your name]], onSuccess() is not called, and onError() is called without arguments.

Reproducible Example
If you can please provide a reproducible example with Stackbliz, CodeSandbox or any other suitable service

Expected behaviour
A clear and concise description of what you expected to happen.

Screenshots

Desktop (please complete the following information):

• OS: [e.g. iOS] Windows 11
• Browser [e.g. chrome, safari] Chrome
• Version [e.g. 22] 125.0.6422.142

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
Add any other context about the problem here.

[kasvith]

Hi, i still didnt have time to check with FedCM

[kasvith]

related #74