policies: rename "Scope" to "ApplicationScope"

For clarity.

app/policies/application_policy.rb

@@ -34,7 +34,7 @@ class ApplicationPolicy
     false
   end
 
-  class Scope
+  class ApplicationScope
     attr_reader :user, :instructeur, :administrateur, :scope
 
     def initialize(account, scope)

app/policies/champ_policy.rb

@@ -1,5 +1,5 @@
 class ChampPolicy < ApplicationPolicy
-  class Scope < Scope
+  class Scope < ApplicationScope
     def resolve
       if user.present?
         scope

app/policies/type_de_champ_policy.rb

@@ -1,5 +1,5 @@
 class TypeDeChampPolicy < ApplicationPolicy
-  class Scope < Scope
+  class Scope < ApplicationScope
     def resolve
       if administrateur.present?
         scope