docs: small code indentation adjustment in the README

[guiireal]

I made a small adjustment to the project documentation, fixing some indentations. I'm getting back into contributing to open-source projects and hope to contribute to this wonderful project as well!

[whiskeysockets-bot]

Thanks for your contribution.

The next step is to wait for review and approval to merge it to main repository

The community can help reacting with a thumb up (:thumbsup:) for approval and rocket (:rocket:) for who has tested it.

To test this PR you can run the following command below:

# NPM
npm install @whiskeysockets/baileys@guiireal/Baileys#docs/ajust-readme
# YARN v2
yarn add @whiskeysockets/baileys@guiireal/Baileys#docs/ajust-readme