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

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https://hg.mozilla.org/integration/gaia-central/rev/a6c3b9aadedc
Author: Fernando Campo <fernando.campo@o2.com>
Desc: Merge pull request #14024 from fcampo/sms-open-settings-942123

Bug 942123 - Tapping on options>settings doesn't open proper window (r=steveck)

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https://hg.mozilla.org/integration/gaia-central/rev/4e814ff3f7e8
Author: Fernando Campo <fernando.campo@o2.com>
Desc: Bug 942123 - Tapping on options>settings doesn't open proper window