recipes.cfg: Forbid all recipe engine warnings

See also http://crrev.com/c/5889430.

Change-Id: I96b1d16fafd04582d9ef831315cfb8de20362a3f
Reviewed-on: https://pigweed-review.googlesource.com/c/infra/recipes/+/237811
Pigweed-Auto-Submit: Rob Mohr <mohrr@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed-service-accounts.iam.gserviceaccount.com>
Reviewed-by: Oliver Newman <olivernewman@google.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
diff --git a/infra/config/recipes.cfg b/infra/config/recipes.cfg
index 2397c79..aeddeec 100644
--- a/infra/config/recipes.cfg
+++ b/infra/config/recipes.cfg
@@ -27,6 +27,13 @@
     }
   },
   "enforce_test_expected_status": true,
+  "forbidden_warnings": [
+    "CHECKOUT_DIR_DEPRECATED",
+    "CQ_MODULE_DEPRECATED",
+    "JSON_READ_DEPRECATED",
+    "PYTHON2_DEPRECATED",
+    "STEP_NEST_NAME_REQUIRED"
+  ],
   "no_docs": true,
   "project_id": "pigweed",
   "repo_name": "pigweed"