fix unit tests

Author: baileympearson

.github/dependabot.yml

@@ -38,6 +38,9 @@ updates:
       # stay on the supported major version of gcp-metadata
       - dependency-name: "gcp-metadata"
         versions: [">=6.0.0"]
+      # NODE-3773: sinon 19+ breaks the srv polling unit tests
+      - dependency-name: "sinon"
+        versions: ["18.x"]
 
     versioning-strategy: increase
     allow:

package-lock.json

@@ -101,7 +101,7 @@
     "nyc": "^17.1.0",
     "prettier": "^3.5.3",
     "semver": "^7.7.0",
-    "sinon": "^20.0.0",
+    "sinon": "^18.0.1",
     "sinon-chai": "^3.7.0",
     "snappy": "^7.2.2",
     "socks": "^2.8.1",