simdutf: 6.2.1 -> 6.4.2 (#397005)

pkgs/by-name/si/simdutf/package.nix

···
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "simdutf";
-  version = "6.2.1";
+  version = "6.4.2";
 
   src = fetchFromGitHub {
     owner = "simdutf";
     repo = "simdutf";
     rev = "v${finalAttrs.version}";
-    hash = "sha256-nWJOqMCP75E9E0fZ63OILroDS4bUMrJPM7h2IQ0K+aU=";
+    hash = "sha256-at1MBvbsgu7Z7UJQqVaakT1Ux16jJVP5JSVubrqF7VY=";
   };
 
   # Fix build on darwin