docs: add filtered by ACLs header curl example

website/content/api-docs/index.mdx

@@ -106,6 +106,27 @@ of results, because some have been filtered out by ACL policies.
 In order to limit information leakage, this header is only present for requests
 authenticated by a valid ACL token.
 
+The following example uses `curl` to view the
+`X-Consul-Results-Filtered-By-ACLs` response header.
+
+```shell-session
+$ curl \
+    --header "X-Consul-Token: <non-anonymous consul token>" \
+    --include \
+    http://127.0.0.1:8500/v1/catalog/services
+
+HTTP/1.1 200 OK
+Content-Type: application/json
+...
+X-Consul-Default-Acl-Policy: deny
+X-Consul-Results-Filtered-By-Acls: true
+
+{
+  "redis": [],
+  "postgresql": ["primary", "secondary"]
+}
+```
+
 ## UUID Format
 
 UUID-format identifiers generated by the Consul API use the