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

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https://hg.mozilla.org/integration/gaia-central/rev/08deb3838e3c
Author: Carsten Book <tomcat@mozilla.com>
Desc: Merge pull request #24736 from mancas/bug1074051

Bug 1074051 - [Settings] sound volume is not changed r=arthurcc

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https://hg.mozilla.org/integration/gaia-central/rev/47e913ac83a1
Author: Manuel Casas Barrado <manuel.casasbarrado@telefonica.com>
Desc: Bug 1074051 - [Settings] sound volume is not changed.r=arthur.chen
Bumping manifests a=b2g-bump