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

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https://hg.mozilla.org/integration/gaia-central/rev/dfce34a13575
Author: Eric O'Connor <eric@bocoup.com>
Desc: Bug 898354 - [User Story] Timer Notification

Add mozAlarms to the timer panel.

Signed-off-by: Mike Pennisi <mike@mikepennisi.com>