Backport of docs: Fix ServiceDefaults example in distributed tracing …

…into release/1.16.x (#18973)

backport of commmit 38c356c

Co-authored-by: Andrea Scarpino <andrea@scarpino.dev>

website/content/docs/connect/distributed-tracing.mdx

@@ -214,7 +214,7 @@ config to take effect.
 
    ```yaml
    apiVersion: consul.hashicorp.com/v1alpha1
-   kind: ProxyDefaults
+   kind: ServiceDefaults
    metadata:
      name: service-name
    spec: