Fix `print_certificate_digest` running on local server

common/src/network/server_webtransport.rs

@@ -43,18 +43,18 @@ impl Command for StartWebTransportServerCommand {
     }
 }
 
-pub(crate) fn print_certificate_digest(
+pub(super) fn print_certificate_digest(
-    event: On<Add, Started>,
+    event: On<Add, WebTransportServerIo>,
     servers: Query<&WebTransportServerIo>,
-) -> Result {
+) {
     let server = event.entity;
-    let certificate = &servers.get(server)?.certificate;
+
-    let certificate_hash = certificate.certificate_chain().as_slice()[0].hash();
+    // SAFETY: Event guarantees the component exists on the entity.
+    let certificate = &servers.get(server).unwrap().certificate;
+    let certificate_hash = &certificate.certificate_chain().as_slice()[0].hash();
     let certificate_digest = certificate_hash.to_string().replace(':', "");
 
     info!("== Certificate Digest ==");
     info!("  {certificate_digest}");
     info!("  (Clients use this to securely connect to the server.)");
-
-    Ok(())
 }