merge_pr_49354

CHIPS subframe navigation web-platform test breakage

Turns out it wasn't our fault! Fixing cookie clearing in the CHIPS wpt

Differential Revision: https://phabricator.services.mozilla.com/D227862

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1929099
gecko-commit: 3ebf3eaa4194343621a222ff73d6eda673cfb51e
gecko-reviewers: timhuang