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

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https://hg.mozilla.org/integration/gaia-central/rev/5e508da44d21
Author: Francisco Jordano <arcturus@ardeenelinfierno.com>
Desc: Merge pull request #12175 from acperez/bug-915722

Bug 915722 - Remove invalid json for wallpaper mcc/mnc customization. r=arcturus

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https://hg.mozilla.org/integration/gaia-central/rev/fc5ed3b06707
Author: Albert <acperez@tid.es>
Desc: Bug 915722 - Remove invalid json for wallpaper mcc/mnc customization. r=arcturus