treewide: with stdenv.lib; in meta -> with lib;

Part of: https://github.com/NixOS/nixpkgs/issues/108938

meta = with stdenv.lib;

is a widely used pattern. We want to slowly remove
the `stdenv.lib` indirection and encourage people
to use `lib` directly. Thus let’s start with the meta
field.

This used a rewriting script to mostly automatically
replace all occurances of this pattern, and add the
`lib` argument to the package header if it doesn’t
exist yet.

The script in its current form is available at
https://cs.tvl.fyi/depot@2f807d7f141068d2d60676a89213eaa5353ca6e0/-/blob/users/Profpatsch/nixpkgs-rewriter/default.nix

pkgs/development/python-modules/weasyprint/default.nix

@@ -11,7 +11,7 @@
   glib,
   pango,
   fontconfig,
-  stdenv,
+  lib, stdenv,
   pytest,
   pytestrunner,
   pytest-isort,
@@ -62,7 +62,7 @@ buildPythonPackage rec {
     sha256 = "0rwf43111ws74m8b1alkkxzz57g0np3vmd8as74adwnxslfcg4gs";
   };
 
-  meta = with stdenv.lib; {
+  meta = with lib; {
     homepage = "https://weasyprint.org/";
     description = "Converts web documents to PDF";
     license = licenses.bsd3;