Add beta label to h1 and adjust meta title

Author: RebeccaTamachiro

src/content/docs/dns/internal-dns/index.mdx

@@ -1,12 +1,15 @@
 ---
 pcx_content_type: overview
-title: Internal DNS
+title: Internal DNS (beta)
 sidebar:
   order: 14
   label: Overview
   group:
     badge:
       text: Beta
+head:
+  - tag: title
+    content: Internal DNS
 ---
 
 import { Render, Description, Plan, RelatedProduct, DirectoryListing, GlossaryTooltip } from "~/components";