Replace package uglifyjs-webpack-plugin with terser-webpack-plugin

The UglifyJS webpack plugin was deprecated in December 2019: https://github.com/webpack-contrib/uglifyjs-webpack-plugin

By switching to Terser we can also unblock future upgrades to Node.js 16+ due to OpenSSL changes

https://stackoverflow.com/questions/69692842/error-message-error0308010cdigital-envelope-routinesunsupported

Author: colinrotherham

dist/accessible-autocomplete.min.js

@@ -77,7 +77,7 @@
     "sinon-chai": "^3.2.0",
     "source-map-loader": "^1.1.3",
     "standard": "^12.0.1",
-    "uglifyjs-webpack-plugin": "^2.0.1",
+    "terser-webpack-plugin": "^4.2.3",
     "webdriverio": "^7.16.13",
     "webpack": "^4.46.0",
     "webpack-cli": "^3.3.12",

dist/accessible-autocomplete.min.js.map

@@ -1,7 +1,7 @@
 import webpack from 'webpack'
 import path from 'path'
 import CopyWebpackPlugin from 'copy-webpack-plugin'
-import UglifyJsPlugin from 'uglifyjs-webpack-plugin'
+import TerserPlugin from 'terser-webpack-plugin'
 const ENV = process.env.NODE_ENV || 'development'
 
 const plugins = [
@@ -22,18 +22,19 @@ const config = {
 
   optimization: {
     minimize: ENV === 'production',
-    minimizer: [new UglifyJsPlugin({
-      cache: true,
-      parallel: true,
+    minimizer: [new TerserPlugin({
+      extractComments: true,
       sourceMap: true,
-      uglifyOptions: {
-        compress: {
-          negate_iife: false,
-          properties: false
+      terserOptions: {
+        format: { comments: false },
+
+        // Include sources content from dependency source maps
+        sourceMap: {
+          includeSources: true
         },
-        output: {
-          comments: false
-        }
+
+        // Compatibility workarounds
+        safari10: true
       }
     })]
   },