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

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https://hg.mozilla.org/integration/gaia-central/rev/adf4120314a9
Author: Yoshi Huang <allstars.chh@mozilla.com>
Desc: Merge pull request #18407 from allstarschh/Bug997623

Bug 997623 - NFC: typo for NDEF_FORMATABLE. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/8551a184a46a
Author: Yoshi Huang <allstars.chh@mozilla.com>
Desc: Bug 997623 - NFC: typo for NDEF_FORMATABLE. r=alive
Bumping manifests a=b2g-bump