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

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https://hg.mozilla.org/integration/gaia-central/rev/a003d22a5ee4
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Merge pull request #18549 from jonallengriffin/browserarg

Bug 999747 - Add --browser-arg support to Gaia unit Python runner, r=ahal

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https://hg.mozilla.org/integration/gaia-central/rev/e685b417b182
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Bug 999747 - Add --browser-arg support to Gaia unit Python runner, r=ahal
Bumping manifests a=b2g-bump