Add liniting

[(ツ)_/¯Kiafuka]

Is your feature request related to a problem? Please describe.
This request is not attached to a functional problem, yet it is related to an environmental problem. I've noticed that we don't have any standard coding style enforcement in place thus this makes the devs working on this project to push relying on their code editors' default configuration which causes inconsistency on the final code.

Describe the solution you'd like
The possible solution would be to configure eslint on the project and select one of the available styles for code and style enforcement. (Preferably use Airbnb or standard configurations).

Describe alternatives you've considered
Alternatively, we could configure Prettier to enforce that we all have the same code style, yet it does have its limitations.

Additional context
N/A.