Bump @vue/cli-service from 3.8.3 to 3.8.4 (#90)

Bumps [@vue/cli-service](https://github.com/vuejs/vue-cli/tree/HEAD/packages/@vue/cli-service) from 3.8.3 to 3.8.4.
- [Release notes](https://github.com/vuejs/vue-cli/releases)
- [Changelog](https://github.com/vuejs/vue-cli/blob/dev/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vue-cli/commits/v3.8.4/packages/@vue/cli-service)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -10,7 +10,7 @@
   "dependencies": {
     "@vue/cli-plugin-babel": "^3.8.0",
     "@vue/cli-plugin-eslint": "^3.7.0",
-    "@vue/cli-service": "^3.8.3",
+    "@vue/cli-service": "^3.8.4",
     "animate.css": "^3.7.0",
     "axios": "^0.18.0",
     "bootstrap": "^4.3.1",