Merge pull request #10732 from mozilla/pyup-update-pyzmq-17.1.2-to-18.0.0

Update pyzmq to 18.0.0

requirements/perftests.txt

@@ -1,6 +1,6 @@
 # Required by locust, not using hashes for now. We'll use them once we can
 # use a tagged locust release
-pyzmq==17.1.2
+pyzmq==18.0.0
 
 # We need this specific commit until there is a new locust release. Once this happens
 # This can be pinned to a specific version.