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

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https://hg.mozilla.org/integration/gaia-central/rev/aecdb3f6cbde
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Merge pull request #15856 from dmarcos/bug961620

Bug 961620 - Pick activity sends the first picture taken instead of the ...

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https://hg.mozilla.org/integration/gaia-central/rev/a3a8b1f2eacb
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Bug 961620 - Pick activity sends the first picture taken instead of the last one
Bumping manifests a=b2g-bump