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

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https://hg.mozilla.org/integration/gaia-central/rev/2c53b2d94fe9
Author: Amir Nissim <amirnissim@gmail.com>
Desc: Merge pull request #13120 from EverythingMe/929437-queryIndex-no-tags

Bug 929437 - [e.me][bug] Unrelated installed apps appear in Collections ...

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https://hg.mozilla.org/integration/gaia-central/rev/4be043bfa51a
Author: Amir Nissim <amirnissim@gmail.com>
Desc: Bug 929437 - [e.me][bug] Unrelated installed apps appear in Collections [r=ranbena]