fix 404 error typo/grammar

Author: Brian Swank

lib/serve.js

@@ -189,7 +189,7 @@ exports.listen = function(port, static, timeout) {
     res
       .status(404)
       .send(
-        `You have requested the root of http://localhost:${port}. This is likely a mistake. netlify-lambda serves functions at htttp://localhost:${port}/.netlify/functions/your-function-name, please fix your code.`
+        `You have requested the root of http://localhost:${port}. This is likely a mistake. netlify-lambda serves functions at http://localhost:${port}/.netlify/functions/your-function-name; please fix your code.`
       );
   });
   app.all("*", createHandler(dir, static, timeout));