Rendering empty_form crashes when empty_permitted is passed to form_kwargs

Description

Issue
When explicitly setting form_kwargs = {'empty_permitted':True} or form_kwargs = {'empty_permitted':False} , a KeyError occurs when rendering a template that uses a formset's empty_form.
Expected Behavior
empty_permitted is ignored for formset.empty_form since empty_permitted is irrelevant for empty_form, as empty_form is not meant to be used to pass data and therefore does not need to be validated.
Steps to Reproduce

views.py

from django.shortcuts import render
from .models import MyModel
def test_view(request):
context = {}
ff = modelformset_factory(MyModel, fields = ['a_field'])
context['formset'] = ff(
queryset = MyModel.objects.none(),
form_kwargs = {'empty_permitted':True} # or form_kwargs = {'empty_permitted':False}
)
return render(request, 'my_app/my_model_formset.html', context)

urls.py

from django.urls import path, include
from .views import test_view
urlpatterns = [
path('test', test_view)
]

my_model_formset.html

{% extends "my_app/base.html" %}
{% block content %}
<form id="my-form" method="post">
{% csrf_token %}
{{ formset }}
<input type="submit" value="Save">
</form>
{{ formset.empty_form }}
{% endblock %}