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

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https://hg.mozilla.org/integration/gaia-central/rev/817f0b704bf0
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12666 from viorelaioia/bug_923448

Bug 923448 - In test_clock_turn_on_off_alarm.py remove the sleep and add a wait_for_checkbox_state_to_change

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https://hg.mozilla.org/integration/gaia-central/rev/fa890dbcc49a
Author: Viorela Ioia <viorelaioia@gmail.com>
Desc: Bug 923448 - In test_clock_turn_on_off_alarm.py remove the sleep and add a wait_for_checkbox_state_to_change