Update Swift version badge to 6.1+

Author: ezefranca

README.md

@@ -2,7 +2,7 @@
 
 <p align="center">
   <img src="https://img.shields.io/badge/platforms-iOS%2015%2B%20%7C%20macOS%2012%2B%20%7C%20tvOS%2015%2B%20%7C%20watchOS%208%2B%20%7C%20visionOS%201%2B-blue.svg" alt="Platforms" />
-  <img src="https://img.shields.io/badge/Swift-5.9%2B-orange.svg" alt="Swift 5.9+" />
+  <img src="https://img.shields.io/badge/Swift-6.1%2B-orange.svg" alt="Swift 6.1+" />
   <img src="https://img.shields.io/badge/SPM-compatible-brightgreen.svg" alt="Swift Package Manager" />
   <img src="https://img.shields.io/badge/License-MIT-lightgrey.svg" alt="MIT License" />
 </p>