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

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https://hg.mozilla.org/integration/gaia-central/rev/dc076c74d0a0
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #15232 from Archaeopteryx/settings-unifyStyles-bug958975

Bug 958975 - [settings] sim manager: "outgoing call" should be plural, unify quotes of “Manage certificates". r=arthurcc

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https://hg.mozilla.org/integration/gaia-central/rev/79ab06eebd68
Author: Sebastian Hengst <archaeopteryx@coole-files.de>
Desc: Bug 958975 - [settings] sim manager: "outgoing call" should be plural, unify quotes of “Manage certificates"