Update README.md

Author: daisuke-t-jp

README.md

@@ -5,8 +5,7 @@
 [![CocoaPods](https://img.shields.io/cocoapods/v/xxHash-Swift.svg)](https://cocoapods.org/pods/xxHash-Swift)
 [![Carthage compatible](https://img.shields.io/badge/Carthage-compatible-green.svg)](https://github.com/Carthage/Carthage)
 [![SwiftPM compatible](https://img.shields.io/badge/SwiftPM-compatible-green.svg)](https://github.com/apple/swift-package-manager)
-[![Build Status](https://travis-ci.org/daisuke-t-jp/xxHash-Swift.svg?branch=master)](https://travis-ci.org/daisuke-t-jp/xxHash-Swift)
-
+![Build Status](https://github.com/daisuke-t-jp/xxHash-Swift/actions/workflows/ci.yml/badge.svg)
 
 # Introduction