Update 'get_url.js'

get_url.js

@@ -9,7 +9,7 @@ xhr.onreadystatechange = () => {
             const flag = xhr.responseText
             window.location.href = 'http://www.wechall.net/challenge/training/programming1/index.php?answer=' + flag
         } else {
-            console.log("Error: "+ xhr.status)
+            console.log('Error: '+ xhr.status)
         }
     }
 }