Update alarmclock.js

Author: joanne342

Sprint-3/alarmclock/alarmclock.js

@@ -20,7 +20,7 @@ function setAlarm() {
 
         if (inputSeconds <= 0) {
             clearInterval(timer);
-            playAlarm();
+            window.playAlarm();
         }
     }, 1000);
 }
@@ -50,6 +50,8 @@ function playAlarm() {
   audio.play();
 }
 
+window.playAlarm = playAlarm;
+
 function pauseAlarm() {
   audio.pause();
 }