invitations_controller doesn't take per-model allow_insecure_sign_in_after_accept

[pcrama]

Due to the usage of Devise.allow_insecure_sign_in_after_accept (instead of resource.allow_insecure_sign_in_after_accept?) in update, it is useless to use devise :invitable, allow_insecure_sign_in_after_accept: false in my model to override the global default for that model only.

Yet the use of Devise::Models.config in models.rb suggests it should be possible.

Note that this issue is there since a long time (I encountered it in v1.6.1): backporting the fix would be greatly appreciated!

[scambra]

Backported to new branch 1-7-stable