feat(proxy): Return prefixed errors to testodrome (#11561)

Testodrome measures uptime based on the failed requests and errors. In
case of testodrome request we send back error based on the service. This
will help us distinguish error types in testodrome and rely on the
uptime SLI.

proxy/src/binary/pg_sni_router.rs

@@ -258,7 +258,7 @@ async fn ssl_handshake<S: AsyncRead + AsyncWrite + Unpin>(
                 "unexpected startup packet, rejecting connection"
             );
             stream
-                .throw_error_str(ERR_INSECURE_CONNECTION, crate::error::ErrorKind::User)
+                .throw_error_str(ERR_INSECURE_CONNECTION, crate::error::ErrorKind::User, None)
                 .await?
         }
     }