Log session table at debug level

The per-packet session dump is too noisy at info.

src/bin/rust-bfdd.rs

@@ -1152,7 +1152,7 @@ impl Bfdd {
                             warn!("Failed to parse packet");
                         }
 
-                        info!(
+                        debug!(
                             "configured sessions: {}",
                             future::join_all(self.sessions_by_discr.values().map(
                                 |session| async { session.get_stats().await.unwrap().to_string() }