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

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https://hg.mozilla.org/integration/gaia-central/rev/ebfac0991702
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Merge pull request #25775 from millermedeiros/1091453-intermittent-single-day

Bug 1091453 - [Calendar] intermittent failure on day observer and single day unit tests r=asutherland

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https://hg.mozilla.org/integration/gaia-central/rev/a44796a31f91
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Bug 1091453 - [Calendar] fix intermittent failures related to db.connection and DayObserver
Bumping manifests a=b2g-bump