Remove unused import from gl_dropdown.js

ee/spec/frontend/pages/admin/application_settings/ci_cd/ci_template_spec.js

 import CiTemplate from 'ee/pages/admin/application_settings/ci_cd/ci_template';
 import { setHTMLFixture } from 'helpers/fixtures';
-import GLDropdown from '~/gl_dropdown'; // eslint-disable-line no-unused-vars
+import '~/gl_dropdown';
 
 const DROPDOWN_DATA = {
   Instance: [{ name: 'test', id: 'test' }],

ee/spec/frontend/projects/settings/access_dropdown_spec.js

 import $ from 'jquery';
-import GLDropdown from '~/gl_dropdown'; // eslint-disable-line no-unused-vars
+import '~/gl_dropdown';
 import AccessDropdown from 'ee/projects/settings/access_dropdown';
 import { LEVEL_TYPES } from 'ee/projects/settings/constants';
 

spec/frontend/pages/projects/pipeline_schedules/shared/components/timezone_dropdown_spec.js

 import $ from 'jquery';
-import GLDropdown from '~/gl_dropdown'; // eslint-disable-line no-unused-vars
+import '~/gl_dropdown';
 import TimezoneDropdown, {
   formatUtcOffset,
   formatTimezone,