cmd/go/internal/work: properly ignore error
cmd/go/internal/work: properly ignore error

Change-Id: Id0e8d170730d946b60c661d90bc98d0ca7545391
GitHub-Last-Rev: 19fed775b7e87c8c721b4487458354a2d5532a6c
GitHub-Pull-Request: golang/go#30001
Reviewed-on: https://go-review.googlesource.com/c/160425
Reviewed-by: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
Run-TryBot: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

nawawi/go,josharian/go,golang/go,golang/go,cloudflare/go,golang/go,cloudflare/go,akutz/go,josharian/go,nawawi/go,CAFxX/go,josharian/go,CAFxX/go,akutz/go,cloudflare/go,josharian/go,akutz/go,akutz/go,josharian/go,cloudflare/go,CAFxX/go,CAFxX/go,CAFxX/go,nawawi/go,josharian/go,akutz/go,josharian/go,golang/go,golang/go,akutz/go,nawawi/go,akutz/go,CAFxX/go,josharian/go,nawawi/go,CAFxX/go,nawawi/go,nawawi/go,golang/go,akutz/go,golang/go,cloudflare/go,cloudflare/go,cloudflare/go,golang/go,CAFxX/go,cloudflare/go,nawawi/go