Ekstra info feltet ved invitationer skal være optional

members/admin/admin_actions.py

@@ -67,7 +67,7 @@ class MassInvitationForm(forms.Form):
                 initial=timezone.now() + timedelta(days=30 * 3),
             )
             email_text = forms.CharField(
-                label="Email ekstra info", widget=forms.Textarea
+                label="Email ekstra info", widget=forms.Textarea, required=False
             )
 
         # Lookup all the selected persons - to show confirmation list