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

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https://hg.mozilla.org/integration/gaia-central/rev/df31e1c9cdce
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #23311 from mozfreddyb/bug-1056882

Bug 1056882: disallow cross-origin imports

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https://hg.mozilla.org/integration/gaia-central/rev/ecdee1ec1a7e
Author: Frederik B <fbraun+gh@mozilla.com>
Desc: Bug 1056882: no cross-origin imports, r=kgrandon
Bumping manifests a=b2g-bump