tctl: fix error reporting when server is down

A regresion in #25780 changed text that used to be reported to
standard output to go to the logger instead. Since the logger
output is only visible when the debug flag is set, this caused
a fatal error to go unreported to the user.

Fixes #28129

tool/tctl/common/tctl.go

@@ -199,8 +199,9 @@ func TryRun(commands []CLICommand, args []string) error {
 		if utils.IsUntrustedCertErr(err) {
 			err = trace.WrapWithMessage(err, utils.SelfSignedCertsMsg)
 		}
-		log.Errorf("Cannot connect to the auth server. Is the auth server running on %q? %v",
-			cfg.AuthServerAddresses()[0].Addr, err)
+		fmt.Fprintf(os.Stderr,
+			"ERROR: Cannot connect to the auth server. Is the auth server running on %q?\n",
+			cfg.AuthServerAddresses()[0].Addr)
 		return trace.NewAggregate(&common.ExitCodeError{Code: 1}, err)
 	}