dashboard: revert accidental inclusion of nacl subrepo trybots
dashboard: revert accidental inclusion of nacl subrepo trybots

Fixes golang/go#28582

Change-Id: Ie3bbb9f4dc1a12c5c4a838165c81f5e2a762a9fe
Reviewed-on: https://go-review.googlesource.com/c/147337
Reviewed-by: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@golang.org>

golang/build,golang/build,golang/build,golang/build