fix: add Mocha to global variable

Author: irrationnelle

rollup.config.js

@@ -17,7 +17,8 @@ const config = {
     file: './mocha.js',
     format: 'umd',
     sourcemap: true,
-    name: 'mocha'
+    name: 'mocha',
+    footer: 'window.Mocha = window.mocha.Mocha;'
   },
   plugins: [
     json(),

test/browser-specific/esm.spec.mjs

@@ -3,3 +3,7 @@ import './fixtures/esm.fixture.mjs';
 it('should register a global if it did not fail', function() {
   expect(window.MOCHA_IS_OK, 'to be ok');
 });
+
+it('should has global Mocha', function() {
+  expect(window.Mocha, 'not to be', undefined);
+});