[Terraform provider] - Use a special resource for deployment stage order and clean

For simplest resources using is_before and is_after is sufficient when we create a qovery_deployment_stage resource. But when you want to rationalise and automatise the creation of the qovery environment with modules and list of stages to create, things are not smooth. You can't create a qovery_deployment_stage resource in a for loop and generate is_previous or in_after in same resource. Have a qovery_deployment_stage_order could dissociate the creation of the stage and his order.

Furthermore, when we create a qovery_deployment_stage it simply add it on already existent default stages. Have a clean_default boolean into qovery_deployment_stage or a resource to control these would be a nice to have.