[@xstate/store] Add shallowEqual

[davidkpiano]

The shallowEqual comparator has been added for selector comparison:

import { shallowEqual } from '@xstate/store';
import { useSelector } from '@xstate/store/react';

import { store } from './store';

function MyComponent() {
  const state = useSelector(
    store,
    (s) => {
      return s.items.filter(/* ... */);
    },
    shallowEqual
  );

  // ...
}

[changeset-bot]

🦋 Changeset detected

Latest commit: a7f4fd4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@xstate/store	Minor

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR