Add regression test for guide data archive mode

[Mounika-2604]

Summary

Adds a regression test for the guide data collection archive handling.

Changes

• Added a test for fetch_guide_data_collection_data.
• Verifies that the downloaded .tar.xz archive is opened using r:xz.
• The test protects against regression to the previous r|xz mode.

Testing

• pytest recirq/documentation_utils_test.py -v
• Result: 3 passed

The new test was also verified against the previous r|xz mode and failed as expected.

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[Mounika-2604]

Hi, I have added the regression test for the guide data archive mode.
All CI checks are passing and the Google CLA has been completed.
Please review when convenient. Thank you!

[Mounika-2604]

Hi, I’ve made the requested changes and verified the regression test locally.
The test passes with the corrected behavior and fails with the previous implementation as expected.
Please review the PR when convenient. Thank you!