Lint: stop ignoring package.js (#32021)

.eslintignore

@@ -4,4 +4,3 @@
 /_gh_pages/
 /js/coverage/
 /site/static/sw.js
-/package.js

package.js

@@ -1,16 +1,18 @@
 // package metadata file for Meteor.js
 
+/* eslint-env meteor */
+
 Package.describe({
   name: 'twbs:bootstrap', // https://atmospherejs.com/twbs/bootstrap
   summary: 'The most popular front-end framework for developing responsive, mobile first projects on the web.',
   version: '5.0.0-alpha2',
   git: 'https://github.com/twbs/bootstrap.git'
-});
+})
 
-Package.onUse(function (api) {
-  api.versionsFrom('METEOR@1.0');
+Package.onUse(api => {
+  api.versionsFrom('METEOR@1.0')
   api.addFiles([
     'dist/css/bootstrap.css',
     'dist/js/bootstrap.js'
-  ], 'client');
-});
+  ], 'client')
+})