Replace deprecated imports

Author: todbachman-wf

test/chromedriver_utils.dart

@@ -3,7 +3,7 @@ import 'dart:io';
 
 import 'package:test/test.dart';
 import 'package:webdev_proxy/src/port_utils.dart';
-import 'package:webdriver/io.dart' as wd;
+import 'package:webdriver/async_io.dart' as wd;
 
 const chromeDriverPort = 4444;
 const chromeDriverUrlBase = 'wd/hub';

test/sse_proxy_handler_test.dart

@@ -8,7 +8,7 @@ import 'package:shelf_static/shelf_static.dart';
 import 'package:sse/server/sse_handler.dart';
 import 'package:test/test.dart';
 import 'package:webdev_proxy/src/port_utils.dart';
-import 'package:webdriver/io.dart';
+import 'package:webdriver/async_io.dart';
 
 import 'package:webdev_proxy/src/sse_proxy_handler.dart';