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

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https://hg.mozilla.org/integration/gaia-central/rev/566953ef93e6
Author: Marcus Cavanaugh <m@mcav.com>
Desc: Merge pull request #16909 from mcav/alarm-bar

Bug 979530 - [B2G][Clock] The text alarm in the notification banner is cut off. r=jrburke

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https://hg.mozilla.org/integration/gaia-central/rev/a73b0c548ddd
Author: Marcus Cavanaugh <m@mcav.com>
Desc: Bug 979530 - [B2G][Clock] The text alarm in the notification banner is cutoff
Bumping manifests a=b2g-bump