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

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https://hg.mozilla.org/integration/gaia-central/rev/d8dbcd6ac980
Author: Carmen Jiménez <cjc@tid.es>
Desc: Merge pull request #17346 from mcjimenez/bug978783_v2

Bug 978783 - SV: Data enabled/disabled by default during FTU customized by SIM

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https://hg.mozilla.org/integration/gaia-central/rev/2aecb1ea1de9
Author: Carmen Jimenez Cabezas <cjc@tid.es>
Desc: Bug 978783 - SV: Data enabled/disabled by default during FTU customized by SIM
Bumping manifests a=b2g-bump