onAuthStateChangedMutation should include additional respnse data like additionalUserInfo

Is your feature request related to a problem? Please describe.

Twitter auth includes additionalUserInfo in the response from authentication.

var provider = new this.$fireModule.auth.TwitterAuthProvider()
this.$fire.auth.signInWithPopup(provider)
        .then((result) => {
        console.log(result.additionalUserInfo)
        }

This data is not available through the properties passed to the onAuthStateChangedMutation in the store, which are: authUser and claims

The one data point I was missing was the twitter handle found in result.additionalUserInfo.username

Describe the solution you'd like

pass additionalUserInfo to the onAuthStateChangedMutation

Describe alternatives you've considered

Expose the full response within the onAuthStateChangedMutation for flexibility with other providers if additionalUserInfo is not general across all social-authentications.

nuxt-community / firebase-module