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

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https://hg.mozilla.org/integration/gaia-central/rev/7674d7010c0d
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12725 from bobsilverberg/volume_error

Bug 924412 - Remove audio channels from cleanup routine that are causing the phone to crash, r=bebe

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https://hg.mozilla.org/integration/gaia-central/rev/240462b2edd5
Author: Bob Silverberg <bob.silverberg@gmail.com>
Desc: Bug 924412 - Remove audio channels from cleanup routine that are causing the phone to crash, r=bebe