Another fix for unverified accounts (#2609)

app/controllers/sessions_controller.rb

@@ -89,7 +89,7 @@ class SessionsController < ApplicationController
       return redirect_to(root_path, alert: I18n.t("invalid_login_method")) unless user.greenlight_account?
       # Check that the user has verified their account
       unless user.activated?
-        user.create_activation_token
+        user.create_activation_token if user.activation_digest.nil? 
         return redirect_to(account_activation_path(digest: user.activation_digest))
       end
     end