build(test): recursively find test files; fail on unsupported dependency versions (#425)

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Source-Link: googleapis/synthtool@fdd03c1

Author: yoshi-automation

packages/google-cloud-dns/.mocharc.js

@@ -14,7 +14,8 @@
 const config = {
   "enable-source-maps": true,
   "throw-deprecation": true,
-  "timeout": 10000
+  "timeout": 10000,
+  "recursive": true
 }
 if (process.env.MOCHA_THROW_DEPRECATION === 'false') {
   delete config['throw-deprecation'];

packages/google-cloud-dns/synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-dns.git",
-        "sha": "5cb1793e1b46c4bd3cabf0d4a062df998f54e88f"
+        "sha": "1fb9fef45a261e9f1ff3a067c1748a7c79d5a54c"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "8cf6d2834ad14318e64429c3b94f6443ae83daf9"
+        "sha": "fdd03c161003ab97657cc0218f25c82c89ddf4b6"
       }
     }
   ],