convert coffeescript file to plain old javascript

app/assets/javascripts/subscriptions-toggle.js

@@ -0,0 +1,15 @@
+// Expand/collapse toggling for coach/student group subscriptions.
+// Used in the new user signup flow, to stop too many options being
+// presented.
+
+/* global $ */
+
+$(() =>
+  $(".subscriptions .toggle").click(function (e) {
+    const $section = $(e.target).closest(".subscriptions");
+    const $container = $(".group-container", $section);
+    const $icon = $(".toggle i", $section);
+    $container.slideToggle(400, () => $container.toggleClass("collapsed"));
+    $icon.toggleClass("fa-chevron-right fa-chevron-down");
+  })
+);