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

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https://hg.mozilla.org/integration/gaia-central/rev/4830af61b34d
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Merge pull request #25413 from millermedeiros/1083820-months-day-refactor

Bug 1083820 - [Calendar] update MonthsDay view to use DayObserver r=gaye

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https://hg.mozilla.org/integration/gaia-central/rev/ec6797b35645
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Bug 1083820 - [Calendar] update MonthsDay view to use DayObserver
Bumping manifests a=b2g-bump