fix: security flaw on auth tokens, error handling

lib/new-admin/services/login.js

@@ -1,10 +1,5 @@
 const db = require('../../db')
 
-function checkUser (username) {
-  const sql = 'SELECT * FROM users WHERE username=$1'
-  return db.oneOrNone(sql, [username]).then(value => { return value.password }).catch(() => false)
-}
-
 function validateUser (username, password) {
   const sql = 'SELECT id, username FROM users WHERE username=$1 AND password=$2'
   const sqlUpdateLastAccessed = 'UPDATE users SET last_accessed = now() WHERE username=$1'
@@ -18,6 +13,5 @@ function validateUser (username, password) {
 }
 
 module.exports = {
-  checkUser,
   validateUser
 }