fix: overlay-cilium-up missing $

Author: jpayne3506

hack/aks/Makefile

@@ -191,7 +191,7 @@ overlay-cilium-up: rg-up ipv4 overlay-net-up ## Brings up an Overlay Cilium clus
 		--kubernetes-version $(K8S_VER) \
 		--node-count $(NODE_COUNT) \
 		--node-vm-size $(VM_SIZE) \
-		--load-balancer-outbound-ips (PUBLIC_IPv4) \
+		--load-balancer-outbound-ips $(PUBLIC_IPv4) \
 		--network-plugin azure \
 		--network-dataplane cilium \
 		--network-plugin-mode overlay \