feat: Add fetchFromAllFeeds

[pablo-schmeiser]

This pull request adds support for fetching all feeds at once in the MISP API client and updates the test suite to reflect this new functionality. The main addition is the new fetch_all_feeds method in the pymisp/api.py file, which enables users to retrieve all feeds in a single call. The test suite is also updated to acknowledge the presence of this method.

API Enhancements:

• Added the fetch_all_feeds method to the MISP API client (pymisp/api.py), providing a way to fetch all feeds via the feeds/fetchFromAllFeeds endpoint.

Test Suite Updates:

• Updated the missing_methods test to remove feeds/fetchFromAllFeeds from the list of missing endpoints, as it is now implemented (tests/testlive_comprehensive.py).
• Added a placeholder in the test_feeds test for fetch_all_feeds, noting that it cannot be fully tested because it fetches all events (tests/testlive_comprehensive.py).

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Human Authored: No AI code generators (e.g., GitHub Copilot, ChatGPT, Clause) were used in the creation of this Pull Request.

[Rafiot]

Thank you!