update the README

Author: irevoire

README.md

@@ -108,7 +108,8 @@ struct Movie {
 }
 
 
-fn main() { block_on(async move {
+#[tokio::main(flavor = "current_thread")]
+async fn main() {
     // Create a client (without sending any request so that can't fail)
     let client = Client::new(MEILISEARCH_URL, Some(MEILISEARCH_API_KEY));
 
@@ -124,7 +125,7 @@ fn main() { block_on(async move {
         Movie { id: 5, title: String::from("Moana"), genres: vec!["Fantasy".to_string(), "Action".to_string()] },
         Movie { id: 6, title: String::from("Philadelphia"), genres: vec!["Drama".to_string()] },
     ], Some("id")).await.unwrap();
-})}
+}
 ```
 
 With the `uid`, you can check the status (`enqueued`, `canceled`, `processing`, `succeeded` or `failed`) of your documents addition using the [task](https://www.meilisearch.com/docs/reference/api/tasks#get-task).
@@ -238,11 +239,11 @@ Json output:
 }
 ```
 
-#### Using users customized HttpClient <!-- omit in TOC -->
+#### Customize the `HttpClient` <!-- omit in TOC -->
 
-If you want to change the `HttpClient` you can incorporate using the `Client::new_with_client` method.
-To use it, you need to implement the `HttpClient Trait`(`isahc` is used by default).
-There are [using-reqwest-example](./examples/cli-app-with-reqwest) of using `reqwest`.
+By default, the SDK uses [`reqwest`](https://docs.rs/reqwest/latest/reqwest/) to make http calls.
+The SDK lets you customize the http client by implementing the `HttpClient` trait yourself and
+initializing the `Client` with the `new_with_client` method.
 
 ## 🌐 Running in the Browser with WASM <!-- omit in TOC -->