updated minimum swift version in README

Author: lkora

README.md

@@ -24,7 +24,7 @@ A highly customizable, performant, and lightweight SwiftUI view that displays an
 -   macOS 12.0+
 -   watchOS 8.0+
 -   visionOS 1.0+
--   Swift 5.7+
+-   Swift 5.9+
 
 ## Installation