MINOR: Fix link to Connect OpenAPI spec (#12713)

Reviewers: José Armando García Sancio <jsancio@confluent.io>

docs/connect.html

@@ -327,7 +327,7 @@ listeners=http://localhost:8080,https://localhost:8443</pre>
         <li><code>GET /</code>- return basic information about the Kafka Connect cluster such as the version of the Connect worker that serves the REST request (including git commit ID of the source code) and the Kafka cluster ID that is connected to.
     </ul>
 
-    <p>For the complete specification of the REST API, see the <a href="generated/connect_rest.yaml">OpenAPI documentation</a></p>
+    <p>For the complete specification of the REST API, see the <a href="/{{version}}/generated/connect_rest.yaml">OpenAPI documentation</a></p>
 
     <h4><a id="connect_errorreporting" href="#connect_errorreporting">Error Reporting in Connect</a></h4>