Lighthouse requires Laravel's auth layer even when all endpoints are public

[palypster]

Describe the bug

Lightouse ending up with:
"Argument 2 passed to Illuminate\Auth\SessionGuard::__construct() must be an instance of Illuminate\Contracts\Auth\UserProvider, null given, called in /var/www/html/vendor/laravel/framework/src/Illuminate/Auth/AuthManager.php on line 125",

in case I don't have any auth guard set up (in config/auth.php and I even deleted Laravel's default User model. If this is expected, than it should be written somewhere in the documentation.

Expected behavior/Solution

Lighthouse shouldn't be dependent on Laravel's Auth layer (default guard) until querying authenticated/authorized endpoint.

Steps to reproduce

1. update config/auth.php to disable default guard
2. query any Lighthouse endpoint
3. you see the error

Environment

Lighthouse Version: v4.7.1
Laravel Version: v6.2

[spawnia]

I would be happy to see a PR for this. If it can be done in a non-breaking manner, i am all for it. If not, we can queue it for the next major version.

[spawnia]

You can create a custom GraphQLContext, see #1105 and remove the dependence on guards.