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/189f7dcc9e1151e6714987e26eb7de14c531d3ae Implement 'diff' sub-command in new 'test' command (phajdan.jr@chromium.org)

TBR=iannucci@chromium.org

Change-Id: Iec3f053e6856c3487802bb51e2634050b60da0c2
Recipe-Tryjob-Bypass-Reason: Autoroller
Bugdroid-Send-Email: False
Reviewed-on: https://chromium-review.googlesource.com/468166
Reviewed-by: <recipe-roller@chromium.org>
Commit-Queue: <recipe-roller@chromium.org>

infra/config/recipes.cfg

@@ -3,7 +3,7 @@
   "deps": {
     "recipe_engine": {
       "branch": "master",
-      "revision": "e02889f17c4ac35b7fb99915c5e05a9dde1347c0",
+      "revision": "189f7dcc9e1151e6714987e26eb7de14c531d3ae",
       "url": "https://chromium.googlesource.com/external/github.com/luci/recipes-py.git"
     }
   },