docs(aio): fix "Error handling" section in "HttpClient" (#18821)

Removed additional curly brackets to fix blocks. Also replaced tab with 2 spaces.

PR Close #18821

aio/content/guide/http.md

@@ -126,7 +126,7 @@ http
     err => {
       console.log('Something went wrong!');
     }
-  });
+  );
 ```
 
 #### Getting error details
@@ -152,7 +152,7 @@ http
         console.log(`Backend returned code ${err.status}, body was: ${err.error}`);
       }
     }
-  });
+  );
 ```
 
 #### `.retry()`