misc/cgo/testcshared: run tests in parallel
misc/cgo/testcshared: run tests in parallel

Change-Id: Id1b5939cfcd210a0cb5f61915ce2d077c7fcec11
Reviewed-on: https://go-review.googlesource.com/62592
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
Run-TryBot: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

codestation/go,cloudflare/go,CAFxX/go,josharian/go,polyverse-security/go,josharian/go,akutz/go,Cofyc/go,golang/go,CAFxX/go,golang/go,golang/go,Cofyc/go,cloudflare/go,golang/go,cloudflare/go,nawawi/go,cloudflare/go,akutz/go,akutz/go,cloudflare/go,Cofyc/go,nawawi/go,akutz/go,CAFxX/go,nawawi/go,polyverse-security/go,nawawi/go,akutz/go,polyverse-security/go,CAFxX/go,polyverse-security/go,codestation/go,christopher-henderson/Go,golang/go,nawawi/go,akutz/go,josharian/go,polyverse-security/go,CAFxX/go,Cofyc/go,polyverse-security/go,golang/go,codestation/go,akutz/go,codestation/go,cloudflare/go,golang/go,golang/go,josharian/go,Cofyc/go,codestation/go,CAFxX/go,josharian/go,Cofyc/go,cloudflare/go,Cofyc/go,Cofyc/go,nawawi/go,nawawi/go,polyverse-security/go,akutz/go,josharian/go,codestation/go,josharian/go,nawawi/go,codestation/go,cloudflare/go,polyverse-security/go,CAFxX/go,josharian/go,CAFxX/go,codestation/go