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

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https://hg.mozilla.org/integration/gaia-central/rev/04a3b84edc94
Author: Kyle Machulis <kyle@nonpolynomial.com>
Desc: Merge pull request #21672 from KevinGrandon/bug_1038040_gaiafox_startup_error

Bug 1038040 - Gaia does not run on DEBUG=1 mode

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https://hg.mozilla.org/integration/gaia-central/rev/515792dd6fa8
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1038040 - Gaia does not run on DEBUG=1 mode
Bumping manifests a=b2g-bump