Fixed signup bug

backend/utils/database.js

@@ -1,6 +1,6 @@
 const mysql = require("mysql2");
 
-//Create a pool of connection to allow multiple query happen at the same time
+//Create a pool of connections to allow multiple query happen at the same time
 const pool = mysql.createPool({
   host: "localhost",
   user: "root",
@@ -8,4 +8,5 @@ const pool = mysql.createPool({
   password: "12345678",
 });
 
+//Export a promise for promise-based query
 module.exports = pool.promise();