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

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https://hg.mozilla.org/integration/gaia-central/rev/4f3700990b2e
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #22440 from KevinGrandon/bug_1043689_vertical_homescreen_dragdrop_init

Bug 1043689 - Safeguard against loading multiple dragdrop objects

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https://hg.mozilla.org/integration/gaia-central/rev/d19542045011
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1043689 - Safeguard against loading multiple dragdrop objects r=cwiiis
Bumping manifests a=b2g-bump