fix(dossier): safely remove child champs in apply_diff

app/models/concerns/dossier_clone_concern.rb

@@ -167,9 +167,10 @@ module DossierCloneConcern
     end
 
     champs_to_remove += diff[:removed]
-    champs_to_remove
-      .filter { !_1.child? || !champs_to_remove.include?(_1.parent) }
-      .each do |champ|
+    children_champs_to_remove, root_champs_to_remove = champs_to_remove.partition(&:child?)
+
+    children_champs_to_remove.each(&:destroy!)
+    root_champs_to_remove.each do |champ|
       champ.rows.flatten.each(&:destroy!) if champ.repetition?
       champ.destroy!
     end