package: Replace rollup-plugin-babel-minify with rollup-plugin-terser.

rollup-plugin-babel-minify is deprecated and it was causing and issue
where after minification some of the IE polyfills were not being
minified correctly and were unavaible in the final js file.

Author: microbit-carlos

config/global.d.ts

@@ -23,11 +23,6 @@ declare module 'rollup-plugin-babel' {
   const plugin: RollupPluginImpl<Options>;
   export default plugin;
 }
-declare module 'rollup-plugin-babel-minify' {
-  export interface Options {}
-  const plugin: RollupPluginImpl<Options>;
-  export default plugin;
-}
 
 // =====================∫
 // missing library types

config/rollup.config.js

@@ -4,7 +4,7 @@ import nodeResolve from '@rollup/plugin-node-resolve';
 import json from '@rollup/plugin-json';
 import commonjs from '@rollup/plugin-commonjs';
 import babel from 'rollup-plugin-babel';
-import minify from 'rollup-plugin-babel-minify';
+import { terser } from 'rollup-plugin-terser';
 
 import pkg from '../package.json';
 
@@ -97,9 +97,9 @@ const umdConfig = createUmdConfig({
 const umdConfigMin = createUmdConfig({
   outputFile: pkg.mainMin,
   extraPlugins: [
-    minify({
-      comments: false,
-      sourceMap: true,
+    terser({
+      ecma: 5,
+      safari10: true, // This also includes workarounds for bugs in Safari 11
     }),
   ],
 });