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

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https://hg.mozilla.org/integration/gaia-central/rev/181deb3d3ba3
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #13029 from KevinGrandon/bug_929943_settings_polyfill_removal

Bug 929943 - [Settings] Remove input type=range polyfill r=arthurcc

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https://hg.mozilla.org/integration/gaia-central/rev/67e8e53fa765
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 929943 - [Settings] Remove input type=range polyfill