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

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https://hg.mozilla.org/integration/gaia-central/rev/d14c81c948ce
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #11603 from mcjimenez/bug893800

Bug 893800 - Add a way to install apps on a specific grid position

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https://hg.mozilla.org/integration/gaia-central/rev/d8c12999e865
Author: Carmen Jimenez <macajc@gmail.com>
Desc: Bug 893800 - Add a way to install apps on a specific grid position