Mention Mac advisory in W4 admin tasks

admin/ip-tasks-fragment.md

@@ -100,6 +100,14 @@ But ==as there are no tutorials this week, you have until the next lecture== to
 {{ embed_topic("weeklySchedule.md#deadline-definition", "Admin " + icon_embedding + " Weekly schedule → **Deadline for weekly tasks**", "1", indent=1) }}
 <p/>
 
+</div>
+<div id="cs2103-week4-intro">
+
+<box type="info" icon=":fab-apple:" seamless>
+
+**++Mac users:++** Ensure you have followed the advisory given [here](programmingLanguages.md).
+</box>
+
 </div>
 {#====================================================================================================================
  # CS2113 Weekly Intros