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

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https://hg.mozilla.org/integration/gaia-central/rev/68e95e070dad
Author: pacorampas <b.frv@tid.es>
Desc: Merge pull request #24828 from pacorampas/1078227

Bug 1078227 - Add data-icon option in tabs BB r=arnau

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https://hg.mozilla.org/integration/gaia-central/rev/3eecf59ac0e9
Author: Paco Rampas <pacorampas@gmail.com>
Desc: Bug 1078227 - Add data-icon option in tabs BB
Bumping manifests a=b2g-bump