expat: 2.4.6 -> 2.4.7

[vcunat]

Motivation for this change

This primarily fixes regressions in various other packages after the expat security fixes.

I'm unsure if this should go to staging-next (current iteration) or the next one (staging branch). It rebuilds stdenv on all platforms, but it also fixes some regressions from the expat security update. Note that the commits are based in a way to allow easy merging to either/both branches.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 22.05 Release Notes (or backporting 21.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.

[vcunat]

Oh and the revert in this PR... might better get adjusted? @jonringer: the nose parts should remain?

[vcunat]

On stable it's already being built. b80b398c16

[risicle]

If python3Packages.xmltodict is easily broken by expat, it's worth adding it to expat's passthru.tests.

[vcunat]

Well we could, but as expat rebuilds all stdenvs, the usual workflows won't work so well.

[risicle]

No but it would give manual reviewers a hint that it might be worth checking that package.

[mweinelt]

Feel free to push that change. In the meantime I've tested these changes on my local python-updates tree and it fixes a few regressions of the xml.parsers.expat.ExpatError: out of memory: line 1, column 0 here and there.

[mweinelt]

Can always decide to pick this up for staging-next, but I want this for python-updates now because the number of failing tests is annoying and us hotpatching everything is not going to happen.

[vcunat]

I suspect that this regression is related to expat updates, in case someone wanted to have a closer look: https://hydra.nixos.org/build/169724144