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

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https://hg.mozilla.org/integration/gaia-central/rev/e7b0d65fb83f
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #12561 from snowmantw/issue919858

Bug 919858 - [LockScreen] Enhance the UI experiments when unlocking the phone with one hande

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https://hg.mozilla.org/integration/gaia-central/rev/20efa00c07b0
Author: Greg Weng <snowmantw@gmail.com>
Desc: Bug 919858 - [LockScreen] Enhance the UI experiments when unlocking the phone with one hande