itunes-volume-control: update livecheck

Casks/i/itunes-volume-control.rb

@@ -8,10 +8,11 @@ cask "itunes-volume-control" do
   desc "Control the volume of Apple Music and Spotify using keyboard volume keys"
   homepage "https://github.com/alberti42/Volume-Control"
 
+  # Upstream doesn't use GitHub releases or reliably create tags for new
+  # versions. Instead, we match the file links in the README.
   livecheck do
-    url "https://github.com/alberti42/Volume-Control#versions"
-    regex(%r{href=.*?/VolumeControl[._-]v?(\d+(?:\.\d+)+)\.zip}i)
-    strategy :page_match
+    url "https://raw.githubusercontent.com/alberti42/Volume-Control/main/README.md"
+    regex(/VolumeControl[._-]v?(\d+(?:\.\d+)+)\.zip/i)
   end
 
   auto_updates true