Keychain access group used for the sign-in state

Hi,

This framework stores the user's sign-in information persistently in the keychain storage. From looking at the code, it doesn't set the access group of the query to the keychain, which means according to [Apple's docs](https://developer.apple.com/documentation/security/ksecattraccessgroup) that it will use the first access group.

If the first access group is shared in several apps of the same vendor, this means that the state will be read and written to the same place, which means that one app will get the user state of another app, which is not necessarily the desired result.

Did I understand everything correctly? If so, what's the way to work around it?
Also if that's the case, I suggest to document it explicitly.

Thanks