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

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https://hg.mozilla.org/integration/gaia-central/rev/bf1959ed268c
Author: evelynhung <jj.evelyn@gmail.com>
Desc: Merge pull request #13788 from pivanov/bug-932833

Bug 932833 - [Settings] 1.3 Visual Refresh of Settings icons, r=evelyn

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https://hg.mozilla.org/integration/gaia-central/rev/3da84e9d084c
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Bug 932833 - [Settings] 1.3 Visual Refresh of Settings icons