Bumping gaia.json for 1 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/470dbad83379
Author: Arthur Chen <crh0716@gmail.com>
Desc: Revert "Merge pull request #13158 from crh0716/911701"

This reverts commit a309c93dcef94552cded8a183740ce44d6c1fc7e.