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

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https://hg.mozilla.org/integration/gaia-central/rev/76e2b06e43a8
Author: Yoshi Huang <allstars.chh@mozilla.com>
Desc: Merge pull request #18313 from allstarschh/Bug995101

Bug 995101 - NFC: Don't use nfc-hardware-state-change event to enable/disable NFC. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/1504968ab6b7
Author: Yoshi Huang <allstars.chh@mozilla.com>
Desc: Bug 995101 - Don't use nfc-hardware-state-change event. r=alive
Bumping manifests a=b2g-bump