[release-branch.go1.20] os/signal: skip nohup tests on darwin builders
The new LUCI builders have a temporary limitation that breaks nohup.
Skip nohup tests there.
For #63875.
Fixes #63910.
Cq-Include-Trybots: luci.golang.try:go1.20-darwin-amd64_13
Change-Id: Ia9ffecea7310f84a21f6138d8f8cdfc5e1392307
Reviewed-on: https://go-review.googlesource.com/c/go/+/538698
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
(cherry picked from commit
a334c452731e7becc2dc879e253c7198202af126)
Reviewed-on: https://go-review.googlesource.com/c/go/+/546376
TryBot-Bypass: Carlos Amedee <carlos@golang.org>