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

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https://hg.mozilla.org/integration/gaia-central/rev/2ff8b89f2004
Author: Gareth Aye <gaye@mozilla.com>
Desc: Merge pull request #22092 from millermedeiros/1042422-refresh-disabled

Bug 1042422 - [B2G][Calendar] Refreshing calendar causes events to be pu.lled down for accounts that are disabled r=gaye

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https://hg.mozilla.org/integration/gaia-central/rev/4e684365da93
Author: Miller Medeiros <miller@millermedeiros.com>
Desc: Bug 1042422 - [B2G][Calendar] Refreshing calendar causes events to be pulled down for accounts that are disabled
Bumping manifests a=b2g-bump