webpack.config.js:366 SyntaxError: Unexpected token ) - trailing comma

Caused by the extra comma here, https://gitlab.com/gitlab-org/gitlab-ce/blob/d4867c518f2d72125c619c191fa9577dabb1ae9a/config/webpack.config.js#L365.

It looks like a trailing comma in function parameters is only supported in ES2017 and is available in Node.js 8+. Or if the JS went through babel but this isn't the case with the webpack config.

13:54:46 webpack.1               | /Users/eric/Documents/gitlab/gitlab-development-kit/gitlab/config/webpack.config.js:366
13:54:46 webpack.1               |   );
13:54:46 webpack.1               |   ^
13:54:46 webpack.1               |
13:54:46 webpack.1               | SyntaxError: Unexpected token )
13:54:46 webpack.1               |     at createScript (vm.js:56:10)
13:54:46 webpack.1               |     at Object.runInThisContext (vm.js:97:10)
13:54:46 webpack.1               |     at Module._compile (module.js:542:28)
13:54:46 webpack.1               |     at Object.Module._extensions..js (module.js:579:10)
13:54:46 webpack.1               |     at Module.load (module.js:487:32)
13:54:46 webpack.1               |     at tryModuleLoad (module.js:446:12)
13:54:46 webpack.1               |     at Function.Module._load (module.js:438:3)
13:54:46 webpack.1               |     at Module.require (module.js:497:17)
13:54:46 webpack.1               |     at require (internal/module.js:20:19)
13:54:46 webpack.1               |     at requireConfig (/Users/eric/Documents/gitlab/gitlab-development-kit/gitlab/node_modules/webpack/bin/convert-argv.js:97:18)

---

$ node -v
v6.11.4

cc @mikegreiling