radicle-cli: fix formatting of warning of unconnected node — heartwood

Signed-off-by: Lars Wirzenius liw@liw.fi

     // Fetch from specified seeds, plus our preferred seeds.
     for nid in &settings.seeds {
         if !sessions.iter().any(|s| &s.nid == nid) {
             term::warning("node {nid} is not connected.. skipping");
             term::warning(format!("node {nid} is not connected.. skipping"));
             continue;
         }
         let result = fetch_from(rid, nid, timeout, node)?;