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

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https://hg.mozilla.org/integration/gaia-central/rev/3688c2d05a43
Author: Gareth Aye <gaye@mozilla.com>
Desc: Merge pull request #14915 from gaye/bug-952611-tbpl

Bug 952611 - Disable keypad test since failing on TBPL

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https://hg.mozilla.org/integration/gaia-central/rev/7a4402112113
Author: Gareth Aye <gaye@mozilla.com>
Desc: Disable keypad test since failing on TBPL