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

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https://hg.mozilla.org/integration/gaia-central/rev/848a2d6b0217
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Merge pull request #24572 from millermedeiros/1018833-duplicate-events

Bug 1018833 - Calendar sync duplicates events r=gaye

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https://hg.mozilla.org/integration/gaia-central/rev/d50328338880
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Bug 1018833 - Calendar sync duplicates events
Bumping manifests a=b2g-bump