Re-add slack project settings route

config/routes/project.rb

@@ -551,6 +551,10 @@ constraints(::Constraints::ProjectUrlConstrainer.new) do
           resource :operations, only: [:show, :update]
           resource :integrations, only: [:show]
 
+          resource :slack, only: [:destroy, :edit, :update] do
+            get :slack_auth
+          end
+
           resource :repository, only: [:show], controller: :repository do
             post :create_deploy_token, path: 'deploy_token/create'
             post :cleanup