Use zig cc as the cross compiler

[mauri870]

Zig cc is a drop-in C compiler that is part of the Zig project. It can serve as a replacement for GCC or Clang, simplifying cross-compilation by eliminating the need for a full compiler suite and dedicated cross-compilation toolchains. This can make the process more streamlined and result in smaller container images.

More details at https://andrewkelley.me/post/zig-cc-powerful-drop-in-replacement-gcc-clang.html.

I think it is worth experimenting with it and see if we can get any real benefit. It should be as simple as installing zig in the images and using the right triplet in CC='zig cc -target aarch64-linux-gnu' CXX='zig c++ -target aarch64-linux-gnu'.