Roll recipe dependencies (trivial).

This is an automated CL created by the recipe roller. This CL rolls recipe
changes from upstream projects (recipe_engine) into this repository.

recipe_engine:
  https://crrev.com/6dd9a28312365e28c7e851516829968cce68df1e (tandrii@google.com)
    cq: expose properties to group similar attempts together.

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

TBR=joshuaseaton@google.com, olivernewman@google.com

Recipe-Tryjob-Bypass-Reason: Autoroller
Bugdroid-Send-Email: False
Change-Id: I2dff4a864713bbe2a771fe40eeb25ff8d413c46d
diff --git a/infra/config/recipes.cfg b/infra/config/recipes.cfg
index f04fbe8..a90579b 100644
--- a/infra/config/recipes.cfg
+++ b/infra/config/recipes.cfg
@@ -19,7 +19,7 @@
   "deps": {
     "recipe_engine": {
       "branch": "master",
-      "revision": "f72daca5c12eb4d83d74c25465520380c169c6b2",
+      "revision": "6dd9a28312365e28c7e851516829968cce68df1e",
       "url": "https://chromium.googlesource.com/infra/luci/recipes-py"
     }
   },