Roll recipe dependencies (trivial).

This is an automated CL created by the recipe roller. This CL rolls recipe
changes from upstream projects (e.g. depot_tools) into downstream projects
(e.g. tools/build).


More info is at https://goo.gl/zkKdpD. Use https://goo.gl/noib3a to file a bug
(or complain)

recipe_engine:
  https://crrev.com/2606a110184a3effca282bc1dbed36ee790872bb [doc] add methods to emit proto from Config objects (iannucci@chromium.org)

TBR=iannucci@chromium.org

Change-Id: Ia661948b7a41100beecbf6965c2df5393197c5e3
Recipe-Tryjob-Bypass-Reason: Autoroller
Bugdroid-Send-Email: False
Reviewed-on: https://chromium-review.googlesource.com/454339
Reviewed-by: <recipe-roller@chromium.org>
Commit-Queue: <recipe-roller@chromium.org>

infra/config/recipes.cfg

@@ -5,5 +5,5 @@ deps {
   project_id: "recipe_engine"
   url: "https://chromium.googlesource.com/external/github.com/luci/recipes-py.git"
   branch: "master"
-  revision: "fcd30616c93ac4532e5cfa4324ba5cd18c8b9a76"
+  revision: "2606a110184a3effca282bc1dbed36ee790872bb"
 }