[pt] Localize docs/contributing/localization.md

[vitorvasc]

Description

What needs to be changed?

This issue is part of the Portuguese localization for the pages under the contributing directory.

URL: https://opentelemetry.io/pt/docs/contributing/localization/

What is the name + path of the page that needs changed?

• content/en/docs/contributing/localization.md

How to contribute

1. Read this guide to familiarize yourself with the contribution process.
2. Comment on this issue about which page you want to localize.
3. If you have any questions, let us know at #otel-localization-ptbr.