awscli2: enable building without pip in the environment

[tjni]

Description of changes

This package has a special check that runs prior to building that checks for pip in the environment. We do not need pip in the environment (it's only there right now by coincidence and will be removed soon) as we provide all the dependencies needed through PYTHONPATH. So we need to relax this check from upstream.

I did this in postPatch because it's not clear to me that this is something that should be upstreamed. (It looks like it has been added specifically to address some concern in their environment.)

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/)
• 23.11 Release Notes (or backporting 23.05 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
• Fits CONTRIBUTING.md.

[natsukium]

@ofborg build python310Packages.awscli2