Bumping gaia.json for 2 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/d9d47ef448f7
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12554 from teodosia/update-lockscreen

Bug 922139 - Update lockscreen tests and app object to address to the new design on aurora r=zac

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https://hg.mozilla.org/integration/gaia-1_2/rev/2334618c1feb
Author: Teodosia Pop <teodosia.pop@gmail.com>
Desc: Bug 922139 - Update lockscreen tests and app object to address to the new design on aurora