JWT always created with user.username and not with USERNAME_FIELD

[mapes911]

I ran into an issue where the login_required decorator was always saying that the user was not logged in. After some debugging I realized that it was because I had changed my user model to use email as the USERNAME_FIELD rather than username.

My username was always set to null, so when the JWT was created on this line:

https://github.com/binarytree-software/django-ariadne-jwt/blob/master/django_ariadne_jwt/utils.py#L74

the token created didn't have a user identifier in it.

I was able to get around that by adding this to my user model.

    @property
    def username(self):
        return self.email

Would be great if we could tell the library if we aren't using "username". Or if it could just use the USERNAME_FIELD from the user model.

Thanks!