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

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

[MarkDaoust]

The formatting changes are making this harder to review. Can you revert everything except the actual change?

We try to keep the readme's somewhat in sync across the SDK repos, it's alos a good Idea to mention Europe in the others.

[MarkDaoust]

Thanks!