Docs: update data package README (#17878)

Add a paragraph in Comparison with Redux section, explaining that 
async side-effects solutions are built-in.

packages/data/README.md

@@ -238,6 +238,8 @@ The data module shares many of the same [core principles](https://redux.js.org/i
 
 The [higher-order components](#higher-order-components) were created to complement this distinction. The intention with splitting `withSelect` and `withDispatch` — where in React Redux they are combined under `connect` as `mapStateToProps` and `mapDispatchToProps` arguments — is to more accurately reflect that dispatch is not dependent upon a subscription to state changes, and to allow for state-derived values to be used in `withDispatch` (via [higher-order component composition](/packages/compose/README.md)).
 
+The data module also has built-in solutions for handling asynchronous side-effects, through [resolvers](#resolvers) and [controls](#controls). These differ slightly from [standard redux async solutions](https://redux.js.org/advanced/async-actions) like [`redux-thunk`](https://github.com/gaearon/redux-thunk) or [`redux-saga`](https://redux-saga.js.org/).
+
 Specific implementation differences from Redux and React Redux:
 
 -   In Redux, a `subscribe` listener is called on every dispatch, regardless of whether the value of state has changed.