Fix helper behavior on controller that don't require authentication (rails#53175)

* Fix helper behavior on controller that don't require authentication

* Removing redundant code, addresses feedback from @zzak

Author: gabrielso

railties/lib/rails/generators/rails/authentication/templates/app/controllers/concerns/authentication.rb.tt

@@ -14,7 +14,7 @@ module Authentication
 
   private
     def authenticated?
-      Current.session.present?
+      resume_session
     end
 
     def require_authentication
@@ -23,7 +23,7 @@ module Authentication
 
 
     def resume_session
-      Current.session = find_session_by_cookie
+      Current.session ||= find_session_by_cookie
     end
 
     def find_session_by_cookie