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

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https://hg.mozilla.org/integration/gaia-central/rev/9ab2a346d962
Author: evelynhung <jj.evelyn@gmail.com>
Desc: Merge pull request #13778 from pivanov/bug-939377

Bug 939377 - [Bluetooth] 1.3 Visual Refresh of Bluetooth Icons, r=evelyn

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https://hg.mozilla.org/integration/gaia-central/rev/5fe5f8223fd9
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Bug 939377 - [Bluetooth] 1.3 Visual Refresh of Bluetooth Icons