Introducing Rakuten Set Draft and Validation Workflow

[elliatab]

This PR introduces two significant additions to our project: a draft of the Rakuten set and a new GitHub Actions workflow designed to validate this set.

These changes aim at streamlining our validation processes with the Rakuten set. Below is a detailed overview of the contributions made through this PR:

New Additions:

• Rakuten Set Draft: A preliminary version of the Rakuten set has been added to the sets. This draft is intended to be iteratively refined based on the validation results and feedback from the team.
• Validation Workflow (rakuten-set-checks.yml): A new GitHub Actions workflow has been introduced to automate the validation of the Rakuten set. This workflow is triggered on every push and pull request, ensuring that any changes to the Rakuten set are automatically validated against Google's predefined criteria. The well-known files check is disabled for now.

Added [.gitignore]

• The default github [.gitignore]file for Python projects has been added to ensure that our repository remains clean by excluding unnecessary files generated during development and testing.

[google-cla]

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[github-actions]

It appears you have failed some tests. Here are your results:
There is no provided rationale for https://rakuten.net
Experienced an error when trying to access https://rakuten.co.jp/.well-known/related-website-set.json; error was: Expecting value: line 1 column 1 (char 0)
Experienced an error when trying to access https://rakuten-card.co.jp/.well-known/related-website-set.json; error was: HTTP Error 404: Not Found
Experienced an error when trying to access https://rakuten-sec.co.jp/.well-known/related-website-set.json; error was: <urlopen error [Errno 110] Connection timed out>
Experienced an error when trying to access https://rakuten-bank.co.jp/.well-known/related-website-set.json; error was: <urlopen error [Errno 110] Connection timed out>
Experienced an error when trying to access https://rakuten-insurance.co.jp/.well-known/related-website-set.json; error was: <urlopen error [Errno -5] No address associated with hostname>
Experienced an error when trying to access https://fril.jp/.well-known/related-website-set.json; error was: HTTP Error 404: Not Found
Experienced an error when trying to access https://rakuten.net/.well-known/related-website-set.json; error was: Expecting value: line 1 column 1 (char 0)
Experienced an error when trying to access https://rakuten.com/.well-known/related-website-set.json; error was: HTTP Error 404: Not Found
Experienced an error when trying to access https://rakuten.ne.jp/.well-known/related-website-set.json; error was: <urlopen error [Errno -5] No address associated with hostname>
Experienced an error when trying to access https://rakuten.co.uk/.well-known/related-website-set.json; error was: Expecting value: line 1 column 1 (char 0)
Experienced an error when trying to access https://rakuten.es/.well-known/related-website-set.json; error was: HTTP Error 404: Not Found
Experienced an error when trying to access https://rakuten.fr/.well-known/related-website-set.json; error was: HTTP Error 404: Not Found
The service site https://rakuten.net does not have an X-Robots-Tag in its header
The service site https://rakuten.net has an ads.txt file, this violates the policies for service sites