fix: Syntax Error: Invalid or unexpected token with .png

Author: kengo nakamura

packages/@vue/cli-plugin-unit-jest/generator/index.js

@@ -19,7 +19,8 @@ module.exports = api => {
     ],
     'transform': {
       // process *.vue files with vue-jest
-      '^.+\\.vue$': 'vue-jest'
+      '^.+\\.vue$': 'vue-jest',
+      '.+\\.(css|styl|less|sass|scss|png|jpg|ttf|woff|woff2)$': 'jest-transform-stub'
     },
     // support the same @ -> src alias mapping in source code
     'moduleNameMapper': {

packages/@vue/cli-plugin-unit-jest/package.json

@@ -25,6 +25,7 @@
     "execa": "^0.9.0",
     "jest": "^22.4.3",
     "jest-serializer-vue": "^1.0.0",
+    "jest-transform-stub": "^1.0.0",
     "vue-jest": "^2.5.0"
   },
   "devDependencies": {