misc/cgo/test: skip TestCrossPackageTests on Android
misc/cgo/test: skip TestCrossPackageTests on Android

This test currently fails in the Android builders, with the message
	pkg_test.go:64: go test -short: exec: "go": executable file not found in $PATH
(https://build.golang.org/log/39ec0da5bfb7793359e199cc8e358ca5a8257840)

I was not able to test this change, because I can't get 'gomote
create' to return an instance of anything Android. However, I will
watch the build dashboard after submitting to verify that the fix
works.

Updates #30228

Android appears to lack a 'go' command in the.

Change-Id: Ieacac7f50d19e2cfef2f5d60e79a159e55b5cfa8
Reviewed-on: https://go-review.googlesource.com/c/164097
Run-TryBot: Bryan C. Mills <1c8aad60184261ccede67f5c63a0d2a3bf3c9ff4@google.com>
Reviewed-by: Elias Naur <1d6e1cf70ec6f9ab28d3ea4b27a49a77654d370e@eliasnaur.com>

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