[Vuejs]-Environment variables for production on Gitlab

When you push your app to production, you need to set the env variables on Gitlab and not in your .env which should be .gitignore‘ed anyway.
The .env is essentially used for development purposes, and should not be committed.

To input some env variables on Gitlab, you can go to your https://gitlab.com/your-group/your-project/-/settings/ci_cd and find it there.
You can set KEY to VUE_APP_CI_PROJECT_NAME and Value to my_website.

Deploy again and it should work fine!