Fix deprecated devise syntax

https://stackoverflow.com/questions/37341967/rails-5-undefined-method-fo
r-for-devise-on-line-devise-parameter-sanitizer

app/controllers/users/registrations_controller.rb

@@ -66,7 +66,7 @@ class Users::RegistrationsController < Devise::RegistrationsController
     end
 
     def configure_permitted_parameters
-      devise_parameter_sanitizer.for(:account_update).push(:email)
+      devise_parameter_sanitizer.permit(:account_update, keys: [:email])
     end
 
     def erase_params