unxip: update macOS dependency

This has `depends_on xcode: ["16.0", :build]`, so it isn't possible to
build this on anything older than Sonoma anyway.

We could maybe alternatively drop the `depends_on macos:` line entirely,
but this makes the output of `brew info` more understandable.

Author: carlocab

Formula/u/unxip.rb

@@ -13,7 +13,7 @@ class Unxip < Formula
     sha256                               x86_64_linux:  "e8ce3607ab1d6aeb51833fc2862c38e28068d172d00b865a89cd2d305ebf69a3"
   end
 
-  depends_on macos: :monterey
+  depends_on macos: :sonoma
 
   uses_from_macos "swift", since: :sonoma