Add website hostname as prefix to cookie table CSV

[mayan-000]

Description

This PR adds code to add hostname as a prefix to the cookie table CSV.

Relevant Technical Choices

Testing Instructions

• Open the PSAT panel and open the cookie table.
• Click on the download icon beside the search bar.
• A file should be downloaded and the file name should include hostname as a prefix.
• For eg. website is https://livemint.com, the file should be www-livemint-com-report.csv

Additional Information:

Screenshot/Screencast

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Checklist

• I have thoroughly tested this code to the best of my abilities.
• I have reviewed the code myself before requesting a review.
• This code is covered by unit tests to verify that it works as intended.
• The QA of this PR is done by a member of the QA team (to be checked by QA).

Fixes #688