[1.8.x] Fixed #13015 -- Clarified language about model instances attached to forms.
[1.8.x] Fixed #13015 -- Clarified language about model instances attached to forms.

Backport of a40a34a4b2d79dbf798df538c26222148d42b17c from master

pquentin/django,h4r5h1t/django-hauthy,pquentin/django,h4r5h1t/django-hauthy,h4r5h1t/django-hauthy,pquentin/django,h4r5h1t/django-hauthy