build: update zig installation method
This simplifies the Dockerfile a little , as the zig package (0.12.0) is available on alpine 3.20 https://repology.org/project/zig/versions
parent image is also updated to current rust-toolchain
Signed-off-by: Yorgos Saslis yorgos.work@proton.me
This simplifies the Dockerfile a little , as the zig package (0.12.0) is available on alpine 3.20 https://repology.org/project/zig/versions
parent image is also updated to current rust-toolchain
Signed-off-by: Yorgos Saslis yorgos.work@proton.me
Rebase.