Setup Jest for EE

ee/spec/frontend/.eslintrc.yml

+---
+env:
+  jest/globals: true
+plugins:
+- jest
+settings:
+  import/resolver:
+    jest:
+      jestConfigFile: "jest.config.js"

jest.config.js

@@ -13,10 +13,11 @@ if (process.env.CI) {
 
 // eslint-disable-next-line import/no-commonjs
 module.exports = {
-  testMatch: ['<rootDir>/spec/frontend/**/*_spec.js'],
+  testMatch: ['<rootDir>/spec/frontend/**/*_spec.js', '<rootDir>/ee/spec/frontend/**/*_spec.js'],
   moduleFileExtensions: ['js', 'json', 'vue'],
   moduleNameMapper: {
     '^~(.*)$': '<rootDir>/app/assets/javascripts$1',
+    '^ee(.*)$': '<rootDir>/ee/app/assets/javascripts$1',
     '^helpers(.*)$': '<rootDir>/spec/frontend/helpers$1',
   },
   collectCoverageFrom: ['<rootDir>/app/assets/javascripts/**/*.{js,vue}'],