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

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https://hg.mozilla.org/integration/gaia-central/rev/9faa8ee2bd8c
Author: Yura Zenevich <yura.zenevich@gmail.com>
Desc: Merge pull request #26266 from yzen/bug-1101141

Bug 1101141 - ensuring that only the active card is visible at any time ...

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https://hg.mozilla.org/integration/gaia-central/rev/12b7fde0471f
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 1101141 - ensuring that only the active card is visible at any time in Email app. r=jrburke
Bumping manifests a=b2g-bump