[Onion services] Inform and link to version 2 onion deprecation blog post
In our onion docs, we should inform users that v2 onion deprecation are going to happen very soon: https://blog.torproject.org/v2-deprecation-timeline
In our onion docs, we should inform users that v2 onion deprecation are going to happen very soon: https://blog.torproject.org/v2-deprecation-timeline