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

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https://hg.mozilla.org/integration/gaia-central/rev/7af9c4916409
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12760 from zacc/bug924955

Bug 924955 - Enable tests for Hamachi device

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https://hg.mozilla.org/integration/gaia-central/rev/ee84fdce21b8
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: Bug 924955 - Enable tests for Hamachi device