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://chromium.googlesource.com/infra/luci/recipes-py/+log/537f0cb4e80136462ca2a427b118f180c4e7ad52~..b26ca6d25250558db80f05c8a515fea2c00b0a2a
  537f0cb (yiwzhang@google.com)
      py3: replace os.unsetenv with os.environ.pop
  b26ca6d (yiwzhang@google.com)
      py3: add cffi to vpthon3 spec

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

TBR=olivernewman+trivial-roll@google.com

Recipe-Tryjob-Bypass-Reason: Autoroller
Bugdroid-Send-Email: False
Change-Id: I96870b247c57d22e492fb8b3398a7210015826e9
Reviewed-on: https://fuchsia-review.googlesource.com/c/infra/recipes/+/561641
Reviewed-by: GI Roller <global-integration-roller@fuchsia-infra.iam.gserviceaccount.com>
Commit-Queue: GI Roller <global-integration-roller@fuchsia-infra.iam.gserviceaccount.com>
diff --git a/infra/config/recipes.cfg b/infra/config/recipes.cfg
index 88cb1c3..59f8b54 100644
--- a/infra/config/recipes.cfg
+++ b/infra/config/recipes.cfg
@@ -20,7 +20,7 @@
   "deps": {
     "recipe_engine": {
       "branch": "refs/heads/main",
-      "revision": "60858d08ac9fef6662887e409547f5430ec5d75f",
+      "revision": "b26ca6d25250558db80f05c8a515fea2c00b0a2a",
       "url": "https://chromium.googlesource.com/infra/luci/recipes-py"
     }
   },