Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/de2c586fd09a
Author: vingtetun <21@vingtetun.org>
Desc: Merge pull request #20133 from vingtetun/multiple.attention.screen

Bug 988212 - Support multiple attention screens. r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/77828358820c
Author: Vivien Nicolas <vnicolas@mozilla.com>
Desc: Bug 988212 - Support multiple attention screens. r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/62f7b1d9b335
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Revert "Merge pull request #19943 from millermedeiros/1019617-week-view-am-pm"

This reverts commit 25ce8f290d921884e15f7559c0597f6b7efad419, reversing
changes made to d04b7196fb59834704ef38d400c813b7ea68d755.
Bumping manifests a=b2g-bump