postgresqlPackages: use lib.extendMkDerivation in postgresqlBuildExtension

pkgs/servers/sql/postgresql/postgresqlBuildExtension.nix

···
   nix-update-script,
 }:
 
-args:
+lib.extendMkDerivation {
+  constructDrv = stdenv.mkDerivation;
 
-let
-  postgresqlBuildExtension =
+  excludeDrvArgNames = [
+    "enableUpdateScript"
+  ];
+
+  extendDrvArgs =
     finalAttrs:
     {
       enableUpdateScript ? true,
···
         ''
         + prevAttrs.postInstall or "";
     };
-in
-stdenv.mkDerivation (lib.extends postgresqlBuildExtension (lib.toFunction args))
+}