Mobility 1.3.x returns Hash instead of HashWithIndifferentAccess on Container back end.

[ngobin]

Rails 8.0.1 (and 7.2.2 too), Ruby 3.4.2, JSONB container backend, postgresql, and ActiveRecord.

Mobility 1.2.9:

> myobject.translations.class
=> ActiveSupport::HashWithIndifferentAccess

Mobility 1.3.2

> myobject.translations.class
=> Hash

This is not a huge deal, and straightforward to work around, but it broke some tests during our upgrade from 1.2.9 -> 1.3.2 that had lines like myobject.translations.slice(:en).

Perhaps it is not an issue, but I thought I would bring it up in case this change in behaviour is unintended and likely to have other consequences.