Adding a note about free tier not available in Europe

[Giom-V]

Description of the change

Adding a note about free tier not available in Europe

Motivation

To clarify things for users and align with the other languages.

Type of change

Choose one: Documentation

Checklist

• [X] I have performed a self-review of my code.
• [X] I have added detailed comments to my code where applicable.
• [X] I have verified that my change does not break existing code.
• [X] My PR is based on the latest changes of the main branch (if unsure, please run git pull --rebase upstream main).
• [X] I am familiar with the Google Style Guide for the language I have coded in.
• [X] I have read through the Contributing Guide and signed the Contributor License Agreement.