Add linting to atm-locator microservice

[jashmehta3300]

Problem Statement

ESLint has not been set up for the atm-locator microservice yet. We can extend the Airbnb style guidelines and format the code according to it.

Proposed Solution

It would be great to remove the linting errors in the code.

[jayanthkoduri]

@jashmehta3300 I need to contribute to Open Source as part of my Course work.
Can you please assign me this.