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

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https://hg.mozilla.org/integration/gaia-central/rev/8e269c855d66
Author: Jose Antonio Olivera Ortega <josea.olivera@gmail.com>
Desc: Merge pull request #12741 from jaoo/923161

Bug 923161 - Emergency calls not performed with some no-line SIM cards. r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/76103e1caec0
Author: Jose Antonio Olivera Ortega <josea.olivera@gmail.com>
Desc: Bug 923161 - Emergency calls not performed with some no-line SIM cards. r=etienne