#166163174 add cors in index.js file

[Inclet]

What does this PR do?

This PR add cors module in the index.js file

Description of Task to be completed?

• Import cors in index .js
• add app.use(cors()) in index.js

How should this be manually tested?

• try to fetch data of any route of this repo and you will get data without the server blocking you.
  for example: https://strikers-ah-backend-staging.herokuapp.com/articles/hello-there-devs-3a4e0ef

What are the relevant pivotal tracker stories?

#166163174