Update module github.com/cilium/cilium to v1.18.4 [SECURITY] (#963)

See linode/linode-cloud-controller-manager#496 (comment)

Author: AshleyDumaine

templates/addons/cilium/cilium.yaml

@@ -9,7 +9,7 @@ spec:
   repoURL: https://helm.cilium.io/
   chartName: cilium
   namespace: kube-system
-  version: ${CILIUM_VERSION:=1.18.2}
+  version: ${CILIUM_VERSION:=1.18.4}
   options:
     waitForJobs: true
     wait: true