remove unused

app/assets/javascripts/dispatcher.js

 /* eslint-disable func-names, space-before-function-paren, no-var, prefer-arrow-callback, wrap-iife, no-shadow, consistent-return, one-var, one-var-declaration-per-line, camelcase, default-case, no-new, quotes, no-duplicate-case, no-case-declarations, no-fallthrough, max-len */
-import { s__ } from './locale';
 import projectSelect from './project_select';
 import IssuableIndex from './issuable_index';
 import Milestone from './milestone';