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

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https://hg.mozilla.org/integration/gaia-1_4/rev/847f044991ee
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #21239 from russnicoletti/bug-1028835_v1.4

This reverts commit e4f7bc7bc121d6351959a9578457f9d7f63d7430.
Bumping manifests a=b2g-bump