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

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https://hg.mozilla.org/integration/gaia-central/rev/ed8596cedfd3
Author: James Burke <jrburke@gmail.com>
Desc: Merge pull request #15387 from jrburke/bug960282-email-missing-attachment-name

Bug 960282 - Email missing attachment name r=asuth

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https://hg.mozilla.org/integration/gaia-central/rev/dd03c147dfb2
Author: jrburke <jrburke@gmail.com>
Desc: Bug 960282 - Email missing attachment name