electron_32: fix log spam when building on aarch64-linux

[emilylange]

clang-19 deprecation warnings on aarch64-linux specifically are causing the log grow beyond h.n.o's log limit of 64mb, which in turn causes the build to get killed.

To work around this, likely until electron_32 is EOL in a month, we simply disable those deprecation warnings. We still have another things causing unnecessary logs, but this should be good enough for now.

https://hydra.nixos.org/build/283952243

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• 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/)
• 25.05 Release Notes (or backporting 24.11 and 25.05 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.

[emilylange]

Builds on aarch64-linux and the log file is around 13 MiB (uncompressed) at the end.

We still get

Warning: supplying the --target argument to a nix-wrapped compiler may not work correctly - cc-wrapper is currently not designed with multi-target compilers in mind. You may want to use an un-wrapped compiler instead.

roughtly ~35k times since #323869, but I haven't had time to fix that yet.
But at least with 13 MiB < 64 MB (sic!), the build should no longer get killed on h.n.o 🫠