clean(engagement): remove last pieces of engagement champs

app/assets/stylesheets/forms.scss

@@ -81,9 +81,7 @@
     }
 
     // Move checkbox to the top-left side of the label
-    &.editable-champ-checkbox,
-    // TODO: remove after 20220725075951_migrate_champs_engagement_to_checkbox passed
-    &.editable-champ-engagement {
+    &.editable-champ-checkbox {
       p,
       label {
         padding-left: 28px;

app/components/editable_champ/engagement_component.rb

@@ -1,2 +0,0 @@
-class EditableChamp::EngagementComponent < EditableChamp::EditableChampBaseComponent
-end

app/graphql/types/champ_type.rb

@@ -15,7 +15,7 @@ module Types
           else
             Types::Champs::TextChampType
           end
-        when ::Champs::EngagementChamp, ::Champs::YesNoChamp, ::Champs::CheckboxChamp
+        when ::Champs::YesNoChamp, ::Champs::CheckboxChamp
           Types::Champs::CheckboxChampType
         when ::Champs::DateChamp
           Types::Champs::DateChampType

app/models/champs/engagement_champ.rb

@@ -1,24 +0,0 @@
-# TODO: remove after 20220725075951_migrate_champs_engagement_to_checkbox passed
-# == Schema Information
-#
-# Table name: champs
-#
-#  id                             :integer          not null, primary key
-#  data                           :jsonb
-#  fetch_external_data_exceptions :string           is an Array
-#  private                        :boolean          default(FALSE), not null
-#  rebased_at                     :datetime
-#  row                            :integer
-#  type                           :string
-#  value                          :string
-#  value_json                     :jsonb
-#  created_at                     :datetime
-#  updated_at                     :datetime
-#  dossier_id                     :integer
-#  etablissement_id               :integer
-#  external_id                    :string
-#  parent_id                      :bigint
-#  type_de_champ_id               :integer
-#
-class Champs::EngagementChamp < Champs::CheckboxChamp
-end

app/models/types_de_champ/engagement_type_de_champ.rb

@@ -1,3 +0,0 @@
-# TODO: remove after 20220725075951_migrate_champs_engagement_to_checkbox passed
-class TypesDeChamp::EngagementTypeDeChamp < TypesDeChamp::CheckboxTypeDeChamp
-end