docs: testflight

Author: EyreFree

README.md

@@ -63,6 +63,14 @@ EFQRCode is a lightweight, pure-Swift library for generating stylized QRCode ima
 
 ## Demo Projects
 
+### TestFlight
+
+You can click the `TestFlight` button below to download demo with TestFlight:
+
+<a target='_blank' href='https://testflight.apple.com/join/LixgpwWt'>
+    <img src='https://testflight.apple.com/images/testflight-128x128_2x_27.png' width='128' height='128'/>
+</a>
+
 ### App Store
 
 You can click the `App Store` button below to download demo, support iOS, tvOS and watchOS:

README_CN.md

@@ -66,6 +66,14 @@ EFQRCode 是一个轻量级的、用来生成和识别二维码的纯 Swift 库
 
 ## 示例
 
+### TestFlight
+
+你可以点击下方的 `TestFlight` 按钮下载示例程序：
+
+<a target='_blank' href='https://testflight.apple.com/join/LixgpwWt'>
+    <img src='https://testflight.apple.com/images/testflight-128x128_2x_27.png' width='128' height='128'/>
+</a>
+
 ### 应用商店
 
 你可以点击下方的 App Store 按钮从应用商店下载示例程序，支持 iOS、tvOS 和 watchOS：