Use SSH wrapper only if no username is known otherwise (#137)

wetty.mjs

@@ -40,9 +40,10 @@ function getCommand(socket, sshuser, sshhost, sshport, sshauth, sshkey) {
   const { request } = socket;
   const match = request.headers.referer.match('.+/ssh/.+$');
   const sshAddress = sshuser ? `${sshuser}@${sshhost}` : sshhost;
+  const sshPath = sshuser || match ? 'ssh' : path.join(__dirname, 'bin/ssh');
   const ssh = match ? `${match[0].split('/ssh/').pop()}@${sshhost}` : sshAddress;
   const sshRemoteOptsBase = [
-                            path.join(__dirname, 'bin/ssh'),
+                            sshPath,
                             ssh,
                             '-p',
                             sshport,