Unexpected promise warning with GRAPHILE_ENV=development
### Summary

receiving warning `Load<stepThing>[1] uses a regular (non-async) function for 'execute'; if it never returns a promise and the list it returns never includes a promise then setting...` when the function is async

### Steps to reproduce

`const stepThing = async () => { ... }`

and run as a step

### Expected results

No warning

### Actual results

a warning

### Additional context

tsconfig

` "target": "esnext"`

(output js was `const stepThing = async (opts) => {...}`)