squid: 7.2 -> 7.3

Refer to upstream changelog for specific details:
https://github.com/squid-cache/squid/releases/tag/SQUID_7_3

For nixpkgs this notably includes a regression fix that was previously
fixed with a patch.

pkgs/by-name/sq/squid/package.nix

@@ -16,26 +16,18 @@
   cppunit,
   ipv6 ? true,
   nixosTests,
-  fetchpatch,
 }:
 stdenv.mkDerivation (finalAttrs: {
   pname = "squid";
-  version = "7.2";
+  version = "7.3";
 
   src = fetchurl {
     url = "https://github.com/squid-cache/squid/releases/download/SQUID_${
       builtins.replaceStrings [ "." ] [ "_" ] finalAttrs.version
     }/squid-${finalAttrs.version}.tar.xz";
-    hash = "sha256-Xgd74dg6nmls6NDZ5yOxJzFSIHoJFAS+aKS5qeGMcAM=";
+    hash = "sha256-2twqmjkmzhs7q+qnp9eyHLsIkCWHbao/XBnn62OR3c0=";
   };
 
-  patches = lib.optional (lib.versionOlder finalAttrs.version "7.2.0") (fetchpatch {
-    # Merged upstream PR; fixes the issue of rejecting domain names starting with digits
-    # To remove when 7.3 is released (or 7.2.1, but that doesn't seem likely)
-    url = "https://patch-diff.githubusercontent.com/raw/squid-cache/squid/pull/2283.patch";
-    hash = "sha256-HLGmzrAH5y1sFfFnVeeegRihyn+N7csGX9lVqmCDIHc=";
-  });
-
   nativeBuildInputs = [ pkg-config ];
   buildInputs = [
     perl