Add aria-label attribute to navigation drawer button. (#3157)

Co-authored-by: David Wheatley <hi@davwheat.dev>

framework/core/js/src/common/components/Navigation.js

@@ -93,6 +93,7 @@ export default class Navigation extends Component {
         drawer.show();
       },
       icon: 'fas fa-bars',
+      'aria-label': app.translator.trans('core.lib.nav.drawer_button'),
     });
   }
 }

framework/core/locale/core.yml

@@ -539,6 +539,10 @@ core:
     loading_indicator:
       accessible_label: => core.ref.loading
 
+    # These translations are used in the navigation header.
+    nav:
+      drawer_button: Open Navigation Drawer
+
     # These translations are used as suffixes when abbreviating numbers.
     number_suffix:
       kilo_text: K