refactor(nodejs): move build cop to flakybot (#431)

This PR was generated using Autosynth. 🌈

Synth log will be available here:
https://source.cloud.google.com/results/invocations/79c017af-4fff-4b22-8cb4-5c2208642be6/targets

- [ ] To automatically regenerate this PR, check this box.

Source-Link: googleapis/synthtool@57c23fa

packages/google-cloud-iot/synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-iot.git",
-        "sha": "92d3b5a739d9a0bd527ef538acff3085f2814c01"
+        "sha": "9b971ff5e38a5e7ab979981c05cda78c55e0ee00"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "363fe305e9ce34a6cd53951c6ee5f997094b54ee"
+        "sha": "57c23fa5705499a4181095ced81f0ee0933b64f6"
       }
     }
   ],