test: Update import paths for chromiumos/config protobufs

BUG=chromium:1069877
TEST=CHROMIUMOS_CONFIG_DIR=../../../src/config ./generate.sh

Cq-Depend: chromium:2144905
Change-Id: I9945bccea7fe90581b8cbba40925c8cab0ff033f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2144769
Tested-by: Prathmesh Prabhu <pprabhu@chromium.org>
Reviewed-by: Andrew Lamb <andrewlamb@chromium.org>
6 files changed