Allow duplicate BOM items when duplicating a part (#5347) (#5350)

(cherry picked from commit 6660508)

Co-authored-by: Oliver <oliver.henry.walters@gmail.com>

InvenTree/part/models.py

@@ -2031,10 +2031,6 @@ def copy_bom_from(self, other, clear=True, **kwargs):
             if bom_item.part in my_ancestors and bom_item.inherited:
                 continue
 
-            # Skip if already exists
-            if BomItem.objects.filter(part=self, sub_part=bom_item.sub_part).exists():
-                continue
-
             # Skip (or throw error) if BomItem is not valid
             if not bom_item.sub_part.check_add_to_bom(self, raise_error=raise_error):
                 continue