LLM-as-judge in translation SDK demo notebook

[HareeshBahuleyan]

What's changing

As a part of a demo, I updated the SDK notebook for translation to include LLM as a judge eval.

How to test it

Steps to test the changes:

1. Setup env following: https://github.com/mozilla-ai/lumigator/blob/main/notebooks/README.md
2. Run notebook and check no cells are broken

Additional notes for reviewers

Anything you'd like to add to help the reviewer understand the changes you're proposing.

I already...

• Tested the changes in a working environment to ensure they work as expected
• Added some tests for any new functionality
• Updated the documentation (both comments in code and product documentation under /docs)
• Checked if a (backend) DB migration step was required and included it if required