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

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https://hg.mozilla.org/integration/gaia-central/rev/d9521847f177
Author: Jose Antonio Olivera Ortega <josea.olivera@gmail.com>
Desc: Merge pull request #13223 from jaoo/922177

Bug 922177 - [Settings] Need to add the APNs provided by client provisioning messages to the setting app. r=kaze

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https://hg.mozilla.org/integration/gaia-central/rev/4e5c1a7472d2
Author: Jose Antonio Olivera Ortega <josea.olivera@gmail.com>
Desc: Bug 922177 - [Settings] Need to add the APNs provided by client provisioning messages to the setting app