Changes made in both Readme files (#2016)

Fixes #2012

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### New Pull Request Checklist

- [x] I have read the
[Documentation](https://pub.dev/documentation/dio/latest/)
- [ ] I have searched for a similar pull request in the
[project](https://github.com/cfug/dio/pulls) and found none
- [ ] I have updated this branch with the latest `main` branch to avoid
conflicts (via merge from master or rebase)
- [ ] I have added the required tests to prove the fix/feature I'm
adding
- [x] I have updated the documentation (if necessary)
- [ ] I have run the tests without failures
- [ ] I have updated the `CHANGELOG.md` in the corresponding package

### Additional context and info (if any)

Replaced **IOClientAdapter** to **IOHttpClientAdapter** on both readme
and replaced **BrowserClientAdapter** to **BrowserHttpClientAdapter** on
both readme.

dio/README-ZH.md

@@ -692,7 +692,7 @@ void main() {
 我们通过 `HttpClientAdapter` 将 `Dio` 和 `HttpClient` 解耦，
 这样一来便可以自由定制 HTTP 请求的底层实现。
 Dio 使用 `IOHttpClientAdapter` 作为原生平台默认的桥梁，
-`BrowserClientAdapter` 作为 Web 平台的桥梁。
+`BrowserHttpClientAdapter` 作为 Web 平台的桥梁。
 你可以通过 `HttpClientAdapter()` 来根据平台创建它们。
 
 ```dart
@@ -704,13 +704,13 @@ dio.httpClientAdapter = HttpClientAdapter();
   ```dart
   import 'package:dio/browser.dart';
   // ...
-  dio.httpClientAdapter = BrowserClientAdapter();
+  dio.httpClientAdapter = BrowserHttpClientAdapter();
   ```
 - 对于原生平台：
   ```dart
   import 'package:dio/io.dart';
   // ...
-  dio.httpClientAdapter = IOClientAdapter();
+  dio.httpClientAdapter = IOHttpClientAdapter();
   ```
 
 [示例](../example/lib/adapter.dart) 中包含了一个简单的自定义桥接。

dio/README.md

@@ -717,7 +717,7 @@ There is an example for [customizing Transformer](../example/lib/transformer.dar
 We can use any `HttpClient` not just `dart:io:HttpClient` to make HTTP requests.
 And all we need is providing a `HttpClientAdapter`.
 The default `HttpClientAdapter` for Dio is `IOHttpClientAdapter` on native platforms,
-and `BrowserClientAdapter` on the Web platform.
+and `BrowserHttpClientAdapter` on the Web platform.
 They can be initiated by calling the `HttpClientAdapter()`.
 
 ```dart
@@ -729,13 +729,13 @@ If you want to use platform adapters explicitly:
   ```dart
   import 'package:dio/browser.dart';
   // ...
-  dio.httpClientAdapter = BrowserClientAdapter();
+  dio.httpClientAdapter = BrowserHttpClientAdapter();
   ```
 - For native platforms:
   ```dart
   import 'package:dio/io.dart';
   // ...
-  dio.httpClientAdapter = IOClientAdapter();
+  dio.httpClientAdapter = IOHttpClientAdapter();
   ```
 
 [Here](../example/lib/adapter.dart) is a simple example to custom adapter.