Update minimal-reqwest example

Author: Bastian Gruber

ch_01/hello/Cargo.lock

@@ -1,7 +1,11 @@
+use std::collections::HashMap;
+
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let resp = reqwest::get("https://httpbin.org/ip")
+        .await?
+        .json::<HashMap<String, String>>()
         .await?;
-    println!("{:?}", resp);
+    println!("{:#?}", resp);
     Ok(())
 }