cmd/dist: apply timeout scale even if timeout isn't overridden
The timeout field is documented as being available so that it's possible
to override timeout by setting a non-zero value. If it's left at zero,
we don't need to override the default go test timeout, but we still need
to apply the timeout scale whenever it's something other than 1.
Fixes (via backport) #61468.
Change-Id: I63634e9b3ef8c4ec7f334b5a6b4bf3cad121355c
Reviewed-on: https://go-review.googlesource.com/c/go/+/511567
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>