Remove hack above migrations package

packages/0x.js/test/global_hooks.ts

@@ -1,6 +1,3 @@
-// HACK: This dependency is optional since it is only available when run from within
-// the monorepo. tslint doesn't handle optional dependencies
-// tslint:disable-next-line:no-implicit-dependencies
 import { runMigrationsAsync } from '@0xproject/migrations';
 
 import { deployer } from './utils/deployer';