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

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https://hg.mozilla.org/integration/gaia-central/rev/d228fe42ac11
Author: Sherman Chen <shamenchens@users.noreply.github.com>
Desc: Merge pull request #22670 from shamenchens/Bug1039326-SettingsOverlapElement-2

Bug 1039326 - Update settings app css, r=arthur

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https://hg.mozilla.org/integration/gaia-central/rev/1647bc671039
Author: Sherman Chen <shamen.chens@gmail.com>
Desc: Bug 1039326 - Update settings app css
Bumping manifests a=b2g-bump