feat(deployment): deploy backend and frontend on heroku

[wildan3105]

Provision:

• heroku postgres ✔️
• heroku data for redis ✔️

Deployment steps for backend:

• target /backend directory ⏲️
• configure Procfile for server and backend ✔️

Deployment steps for frontend:

• target /frontend directory ⏲️
• configure Procfile for frontend ⏲️

UPDATE Temporary deployed at: https://google-scraper-web-7922a635d04a.herokuapp.com/ but with development mode for backend and frontend apps

[wildan3105]

Update: There are a couple of challenges when deploying fullstack app to Heroku:

1. Heroku doesn't support deployment based on subdirectory out-of-the-box. This requires some hacky solutions to get around it.
2. The worker dyno could not accept HTTP request that would be used for socket client to connect to the server