This removes all other Bazel test commands, so all tests can be again
tested with `bazel test ...`.
Also, fixes linux-arm64 glibc tests. Until now they've worked only in
CI. Now they work everywhere I tried.
`zig cc` emits `--gc-sections` for the linker, which is incompatbile
with what CGo thinks about linking.
This commit adds a workaround: it will add `--no-gc-sections` to the
linking step if the command is not specified (falling back to the
default behavior of gcc/clang).
Related: https://github.com/golang/go/issues/52690