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

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https://hg.mozilla.org/integration/gaia-central/rev/f1a29d9e7847
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #14968 from yurenju/refactoring-build

Bug 953161 - Move all data in build/ to build/data/ r=@ochameau

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https://hg.mozilla.org/integration/gaia-central/rev/ee39f3d9ba34
Author: Yuren Ju <yurenju@gmail.com>
Desc: Bug 953161 - Move all data in build/ to build/config/