Update docs/quickstart.mdx

Co-authored-by: Till Rohrmann <[email protected]>

docs/quickstart.mdx

@@ -123,7 +123,7 @@ restate dp add http://host.docker.internal:9080
 ```
 
 Or via `curl`, by sending a request to the endpoint of the runtime at `http://localhost:9070/deployments`
-and providing it with the deployment endpoint of the service `http://localhost:9080`.
+and providing it with the deployment endpoint of the service `http://host.docker.internal:9080`.
 ```shell
 curl localhost:9070/deployments -H 'content-type: application/json' -d '{"uri": "http://host.docker.internal:9080"}'
 ```