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

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https://hg.mozilla.org/integration/gaia-central/rev/2b63513acfbf
Author: Fernando Campo <fernando.campo@o2.com>
Desc: Merge pull request #14649 from fcampo/sms-overlay-style-broken-947285

Bug 947285 - [Messaging] Notice style is broken (r=julienw)

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https://hg.mozilla.org/integration/gaia-central/rev/a6211c58e5cf
Author: Fernando Campo <fernando.campo@o2.com>
Desc: Bug 947285 - [Messaging] Notice style is broken