73d92309d7 guix: use GCC 11 for macOS builds (fanquake)
Pull request description:
Note that this is just the native compiler, which is used to build the toolchain we use to build the actual binaries.
Partially motivated by #29091, where it could now be a bit confusing if we are explicitly using GCC 10 in our release toolchain, when our minimum required is 11 (this can't be bumped to 12 due to build issues with native tools).
At the same time, remove `gcc-toolchain "static"` from the macOS build env.
ACKs for top commit:
hebasto:
ACK 73d92309d7.
Tree-SHA512: 31392290b327cc0e19498cf053b7c9eb19e70295933d650b29b29589356ad455d35b6addcdaae702a9635513c07070fb17d61bcb48445d3cb1a9d4a93aa6ddf3