Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/4cbd8c08d0ab
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #25114 from KevinGrandon/bug_1082329_remove_old_tests

Bug 1082329 - Remove unused tests in the tests/ directory

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https://hg.mozilla.org/integration/gaia-central/rev/6a2f6b7bd0bd
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1082329 - Remove unused tests in the tests/ directory r=etienne
Bumping manifests a=b2g-bump