Warning while testing DataGrid which I believe is from useTubular

[nickpalmer]

Describe the bug

While testing a component using DataGrid I am getting the following warning:

console.error ../../node_modules/react-dom/cjs/react-dom.development.js:88
      Warning: Can't perform a React state update on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all subscriptions and asynchronous tasks in a useEffect cleanup function.

To Reproduce
Steps to reproduce the behavior:

1. Write a test which mounts a DataGrid

Expected behavior
There shouldn't be a warning.

I believe this is caused by useTubular calling useEffect() but not returning a cleanup function, so the dispatch when the API call is complete fires after the component is unmounted.

Ideally the processRequest() api could be updated to handle the return of a Future which can be canceled. I will try to put a PR together to fix this, but no promises on timing on that.