Nodes: Remove node after link drag search cancel

Remove the node if the transform operation is cancelled rather than
confirmed. This is consistent with the regular search menu.

source/blender/editors/space_node/link_drag_search.cc

@@ -232,6 +232,7 @@ static void link_drag_search_exec_fn(bContext *C, void *arg1, void *arg2)
   PointerRNA ptr;
   WM_operator_properties_create_ptr(&ptr, ot);
   RNA_boolean_set(&ptr, "view2d_edge_pan", true);
+  RNA_boolean_set(&ptr, "remove_on_cancel", true);
   WM_operator_name_call_ptr(C, ot, WM_OP_INVOKE_DEFAULT, &ptr, nullptr);
   WM_operator_properties_free(&ptr);
 }