Add an API helper to link two elements

Closes #277 (closed)

arkindex_worker/worker/element.py

@@ -306,14 +306,12 @@ class ElementMixin:
             logger.warning("Cannot link elements as this worker is in read-only mode")
             return
 
-        element_parent = self.request(
+        return self.request(
             "CreateElementParent",
             parent=parent.id,
             child=child.id,
         )
 
-        return element_parent
-
     def partial_update_element(
         self, element: Element | CachedElement, **kwargs
     ) -> dict: