Describe the bug
I created two entities using a ManyToMany-relation and want to edit the relation from both of the entites using an AssocationField.
(e.g. User and Group, I want to be able to edit the User and assign it to many groups as well as edit the Group and assign many users to it)
What happens is that the relation is only saved "one way". I added the corresponding field to both CrudControllers, the field is shown on both edit-pages but will only save the relation when the entity is saved that has the "inversedBy"-part. The "mappedBy"-entity will not save the data.
I have tried to add "ORM\JoinTable" but that either result in an "table exists"-error or in two different relation-tables being created (user_group and group_user) which will save the relation but not making it visible to the other entity (so I end up having two ManyToMany-relations).

To Reproduce
Version used is 4.0.2, to reproduce create to entities:

#[ORM\ManyToMany(targetEntity: User::class, inversedBy: 'groups')]
private Collection $users;

#[ORM\ManyToMany(targetEntity: Group::class, mappedBy: 'users')]
private Collection $groups;

Then add the relation as an AssociationField in the CrudControllers:
yield AssociationField::new('users'); in the GroupCrudController and yield AssociationField::new('groups'); in the UserCrudController.