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

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https://hg.mozilla.org/integration/gaia-central/rev/37bde70c6d49
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12923 from zacc/bug-927873

bug 927873 - Python browser tests - offset tap in browser app object to ...

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https://hg.mozilla.org/integration/gaia-central/rev/266364991ada
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: bug 927873 - Python browser tests - offset tap in browser app object to bust the app update notification interrupting the test