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

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https://hg.mozilla.org/integration/gaia-central/rev/a4fc104407a6
Author: Mihai Cîrlănaru <mihai@cirlanaru.com>
Desc: Merge pull request #14189 from mihai/bug_937533

Bug 937533 - [Settings] Update reset phone dialog. r=@crh0716

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https://hg.mozilla.org/integration/gaia-central/rev/3428b672e445
Author: Mihai Cirlanaru <mihai@cirlanaru.com>
Desc: Bug 937533 - [Settings] Update reset phone dialog. r=arthurcc