[v6.0.0-beta3] ObjectPersister argument 3 is null

[boskos-q]

Hi there. I'm using Symfony 5.2.x with FoSElasticaBundle v6.0.0-beta3 and ElasticSearch 7.10.2 I've updated my code but I'm getting the error when running php bin/console lint:container

[ERROR] Invalid definition for service "fos_elastica.object_persister.stats": argument 3 of
         "FOS\ElasticaBundle\Persister\ObjectPersister::__construct()" accepts "string", "null" passed.

My yaml config looks like this

fos_elastica:
    clients:
        default:
            host:      '%elastica.host%'
            port:      '%elastica.port%'
            transport: '%elastica.transport%'
            logger:    '%elastica.logger%'
    indexes:
        stats:
            settings:
                index:
                    max_result_window: 500000
            properties:
                timestamp:
                    type: date
                    format: "yyyy/MM/dd HH:mm:ss||yyyy/MM/dd"
                signupTime:
                    type: date
                    format: "yyyy/MM/dd HH:mm:ss||yyyy/MM/dd"
                expiredTime:
                    type: date
                    format: "yyyy/MM/dd HH:mm:ss||yyyy/MM/dd"
                someMoreFields:
                    ....
            persistence:
                provider:
                    service: '%elastica.stats.provider.service%'

I don't need this to be persisted in the db at all, but rather in the elastic, therefore there is no model that this document can rely on. I've tried setting

listener:
    enabled: false

but without luck. If I were to define some dummy model then all checks are passing.

So the question is, do I really need to define model and/or driver or that can be omitted in this case as I'm not using db for this index ?

Update Might be related to the 2nd part of #1780