Remove expandCollapse.js script and refs to it

app/assets/javascripts/expandCollapse.js

@@ -1,58 +0,0 @@
-(function(Modules) {
-  "use strict";
-
-  Modules.ExpandCollapse = function() {
-
-    this.start = function(component) {
-
-      this.$component = $(component);
-
-      this.$toggle = this.$component.find('.toggle')
-        .on(
-          "click",
-          this.change
-        )
-        .on("keydown", this.filterKeyPresses([32, 13], this.change));
-
-      if (this.getNativeHeight() < this.$component.data('max-height')) {
-        this.change();
-      }
-
-    };
-
-    this.filterKeyPresses = (keys, callback) => function(event) {
-
-      if (keys.indexOf(event.keyCode)) return;
-
-      event.preventDefault();
-      callback();
-
-    };
-
-    this.getNativeHeight = function() {
-
-      var $copy = this.$component.clone().css({
-        'position': 'absolute',
-        'left': '9999px',
-        'width': this.$component.width(),
-        'font-size': this.$component.css('font-size'),
-        'line-height': this.$component.css('line-height')
-      }).addClass('expanded');
-
-      $('body').append($copy);
-
-      var nativeHeight = $copy.height();
-
-      $copy.remove();
-
-      return nativeHeight;
-
-    };
-
-    this.change = () => this.toggleCollapsed() && this.$toggle.remove();
-
-    this.toggleCollapsed = () => this.$component.addClass('expanded');
-
-  };
-
-})(window.GOVUK.Modules);

gulpfile.js

@@ -84,7 +84,6 @@ const javascripts = () => {
       paths.src + 'javascripts/autofocus.js',
       paths.src + 'javascripts/highlightTags.js',
       paths.src + 'javascripts/fileUpload.js',
-      paths.src + 'javascripts/expandCollapse.js',
       paths.src + 'javascripts/radioSelect.js',
       paths.src + 'javascripts/updateContent.js',
       paths.src + 'javascripts/listEntry.js',