Remove reference to local_dash from firmware_test.py

This tool is being deprecated.

BUG=brillo:1067
TEST=None

Change-Id: Ia0d65ba1b749f798a0ecf24d80cee4ad07effecf
Reviewed-on: https://chromium-review.googlesource.com/272215
Tested-by: Christopher Wiley <wiley@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
Commit-Queue: Christopher Wiley <wiley@chromium.org>
1 file changed