Add MetalLB advertisement

clusters/my-cluster/metallb-system/ip-address-pool.yaml

@@ -0,0 +1,9 @@
+---
+apiVersion: metallb.io/v1beta1
+kind: IPAddressPool
+metadata:
+  name: first-pool
+  namespace: metallb-system
+spec:
+  addresses:
+  - 10.100.100.240-10.100.100.250

clusters/my-cluster/metallb-system/kustomization.yaml

@@ -3,3 +3,5 @@ apiVersion: kustomize.config.k8s.io/v1beta1
 kind: Kustomization
 resources:
   - metallb-native.yaml
+  - ip-address-pool.yaml
+  - l2-advertisement.yaml

clusters/my-cluster/metallb-system/l2-advertisement.yaml

@@ -0,0 +1,6 @@
+---
+apiVersion: metallb.io/v1beta1
+kind: L2Advertisement
+metadata:
+  name: example
+  namespace: metallb-system