sweet/benchmarks/go-build: pass through stdout/stderr

In case systemd-run fails, we'd like to see the error in results.

For golang/go#54760.

Change-Id: Id19d938308d25cf37bbb9e129ce1ec9e89ac8726
Reviewed-on: https://go-review.googlesource.com/c/benchmarks/+/426237
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
1 file changed