Also, add a directory parameter to RunGoCommand. To make sure that the
parameters aren't misused, change args to a []string.
Updates golang/go#40340
Change-Id: Ib5ce606a401a18c29c904b570ec9339f067a3961
Reviewed-on: https://go-review.googlesource.com/c/tools/+/245818
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>