ssh remoting: Show the host's GitHub name in the titlebar when sharing an SSH project (#19844)

The name (GitHub name) of the host was not displayed when sharing an ssh
project.

Previously we assumed that the a collaborator is a host if the
`replica_id` of the collaborator was `0`,
but for ssh project the `replica_id` is actually `1`.

<img width="329" alt="Screenshot 2024-10-28 at 18 16 30"
src="https://github.com/user-attachments/assets/c0151e12-a96f-4f38-aec1-4ed5475a9eaf">


Co-Authored-by: Thorsten <thorsten@zed.dev>

Release Notes:

- N/A

---------

Co-authored-by: Thorsten <thorsten@zed.dev>

crates/workspace/src/workspace.rs

@@ -5715,7 +5715,7 @@ pub fn join_in_room_project(
                             .read(cx)
                             .collaborators()
                             .values()
-                            .find(|collaborator| collaborator.replica_id == 0)?;
+                            .find(|collaborator| collaborator.is_host)?;
                         Some(collaborator.peer_id)
                     });