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

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https://hg.mozilla.org/integration/gaia-1_4/rev/984e24bf6b34
Author: Marcus Cavanaugh <m@mcav.com>
Desc: Merge pull request #19339 from mcav/timer-fix

Bug 1009977 - [B2G][Clock] The seconds portion of the timer inconsistent...
Bumping manifests a=b2g-bump