net: convert many Close tests to use parallel subtests
net: convert many Close tests to use parallel subtests

Also set a deadline in TestCloseWrite so that we can more easily
determine which kind of connection is getting stuck on the
darwin-arm64-corellium builder (#34837).

Change-Id: I8ccacbf436e8e493fb2298a79b17e0af8fc6eb81
Reviewed-on: https://go-review.googlesource.com/c/go/+/227588
Run-TryBot: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>

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