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

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https://hg.mozilla.org/integration/gaia-central/rev/3ec0723bdc0e
Author: Albert <acperez@tid.es>
Desc: Merge pull request #13185 from acperez/bug-932223

Bug 932223 - External apps split in two folders during make process. r=yurenju

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https://hg.mozilla.org/integration/gaia-central/rev/81a6f6e59661
Author: Albert <acperez@tid.es>
Desc: Bug 932223 - External apps split in two folders during make process. r=yurenju