make jest happy with "type": "module"

Author: Romex91

jest.config.js

@@ -1,5 +1,8 @@
-module.exports = {
+export default {
   preset: 'ts-jest/presets/js-with-ts',
   testEnvironment: 'jsdom',
   setupFiles: ['<rootDir>/node_package/tests/jest.setup.js'],
+  moduleNameMapper: {
+    '^(\\.{1,2}/.*)\\.js$': '$1'
+  },
 };