devserver: deprecate latestbuild rpc

The provision_Cr50TOT test has been updated to use gs.py. The
latestbuild RPC can not be deprecated.

BUG=chromium:1092689
TEST=None

Cq-Depend: chromium:2341955
Change-Id: I6d6fc85f3e92aeb446001c4e7760bc25e141bf99
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/2340558
Tested-by: Sanika Kulkarni <sanikak@chromium.org>
Auto-Submit: Sanika Kulkarni <sanikak@chromium.org>
Reviewed-by: Congbin Guo <guocb@chromium.org>
Commit-Queue: Sanika Kulkarni <sanikak@chromium.org>
1 file changed