[SSL] Fix incorrect DCV delegation example (#16765)

Author: sfc-gh-hdhillon

src/content/docs/ssl/edge-certificates/changing-dcv-method/methods/delegated-dcv.mdx

@@ -64,7 +64,7 @@ _acme-challenge.example.com CNAME example.com.<COPIED_VALIDATION_URL>.
 For example, a certificate covering `example.com`, `*.example.com`, and `sub.example.com` would require the following records.
 
 ```txt
-_acme-challenge.example.com CNAME .example.com.<COPIED_VALIDATION_URL>.
+_acme-challenge.example.com CNAME example.com.<COPIED_VALIDATION_URL>.
 _acme-challenge.sub.example.com CNAME sub.example.com.<COPIED_VALIDATION_URL>.
 ```