fix: use ingress subdomain instead of ipv4 to better reflect usage

Signed-off-by: Devin Buhl <devin@buhl.casa>

kubernetes/apps/flux-system/addons/webhooks/github/ingress.yaml

@@ -5,7 +5,7 @@ metadata:
   name: flux-webhook
   namespace: flux-system
   annotations:
-    external-dns.alpha.kubernetes.io/target: "ipv4.${SECRET_DOMAIN}"
+    external-dns.alpha.kubernetes.io/target: "ingress.${SECRET_DOMAIN}"
     hajimari.io/enable: "false"
 spec:
   ingressClassName: nginx