Keep in sync with logic in std.Build.addRunArtifact which decides whether
the test runner will communicate with the build runner via std.zig.Server.
const need_simple = switch (builtin.zig_backend)
const need_simple = switch (builtin.zig_backend) {
.stage2_aarch64,
.stage2_powerpc,
.stage2_riscv64,
=> true,
else => false,
}