Empty store throwing exception on Trigger state

[nk-ag]

To Reproduce
Steps to reproduce the behavior:

1. Trigger state with empty store

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots

[nk-ag]

        new_stores = [
            Store(
                run_id=run_id,
                namespace=namespace_name,
                graph_name=graph_name,
                key=key,
                value=value
            ) for key, value in body.store.items()
        ]

        await Store.insert_many(new_stores)