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

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https://hg.mozilla.org/integration/gaia-central/rev/4926fae17784
Author: gitmai <mri@tid.es>
Desc: Merge pull request #16942 from gitmai/bug-979381-CC-add-argument-requestSettings

Bug 979381 - [CostControl] Add a new agument to the 'requestSettings' me...
r=salva

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https://hg.mozilla.org/integration/gaia-central/rev/47572e54b1de
Author: mai <mri@tid.es>
Desc: Bug 979381 - [CostControl] Add a new agument to the 'requestSettings' method, to let specifying for which IccID do the settings refer
Bumping manifests a=b2g-bump