Specify a standard filename under terserOptions

Created by: resting

Is your proposal related to a problem?

The current npm run build extracts the License comments and put them in a file that ends in a non standard extension .LICENCSE. This causes problem for servers like IIS to return 404 for request to the file. It also causes serviceWorker to break due to the file not being loaded.

Describe the solution you'd like

Specify a standard name under terserOptions in webpack.config.js, so that it ends in .js.

Not tested, should be something like the below:

filename: [file]