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

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https://hg.mozilla.org/integration/gaia-central/rev/da612c90be7d
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #15943 from KevinGrandon/bug_967516_enable_device_debug_default

Bug 967516 - Enable DEVICE_DEBUG by default for non production builds

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https://hg.mozilla.org/integration/gaia-central/rev/1216fc698cf9
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 967516 - Enable DEVICE_DEBUG by default for non production builds r=ochameau
Bumping manifests a=b2g-bump