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

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https://hg.mozilla.org/integration/gaia-central/rev/55cc47be6f6c
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #11936 from cctuan/894277

Bug 894277 - It should have a prompt when set the wallpaper from gallery

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https://hg.mozilla.org/integration/gaia-central/rev/c841625704be
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 894277 - It should have a prompt when set the wallpaper from gallery