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

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https://hg.mozilla.org/integration/gaia-central/rev/59dfb682808c
Author: gasolin <gasolin@gmail.com>
Desc: Merge pull request #13277 from MBRSL/bug-931726-gUM

bug - 931726 [HW test] change recording test to gUM test, r=gasolin

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https://hg.mozilla.org/integration/gaia-central/rev/3fe0f100e1b6
Author: Tom Jao <tjao@mozilla.com>
Desc: Bug 931726 - [HW test] change recording test to gUM test, remove audioloop test