Move sign_in behind /manager (not in namespace due to Administrate resources autoloading)

config/routes.rb

@@ -1,4 +1,6 @@
 Rails.application.routes.draw do
+  get 'manager/sign_in' => 'administrations/sessions#new'
+  delete 'manager/sign_out' => 'administrations/sessions#destroy'
   namespace :manager do
     resources :procedures, only: [:index, :show] do
       post 'whitelist', on: :member
@@ -56,9 +58,6 @@ Rails.application.routes.draw do
   get 'users' => 'users#index'
   get 'admin' => 'admin#index'
 
-  get 'administrations/sign_in' => 'administrations/sessions#new'
-  delete 'administrations/sign_out' => 'administrations/sessions#destroy'
-
   resources :stats, only: [:index]
 
   namespace :france_connect do