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

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https://hg.mozilla.org/integration/gaia-central/rev/fad008fdd856
Author: Carsten Book <tomcat@mozilla.com>
Desc: Merge pull request #20511 from guilherme-pg/bug1017832-play-sound-doesnt-play

Bug 1017832 - Properly use 'content' channel for playing sound on Find My Device. r=dflanagan

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https://hg.mozilla.org/integration/gaia-central/rev/389c74b46916
Author: Guilherme Goncalves <guilherme.p.gonc@gmail.com>
Desc: Bug 1017832 - Properly use 'content' channel for playing sound on Find My Device.
Bumping manifests a=b2g-bump