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

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https://hg.mozilla.org/integration/gaia-1_4/rev/691a2603b34d
Author: Marcus Cavanaugh <m@mcav.com>
Desc: Bug 884080 - [email] Reply-to-all does not filter out the active account. r=asuth
Bumping manifests a=b2g-bump