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

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https://hg.mozilla.org/integration/gaia-2_0/rev/ab7efde62822
Author: James Lal <james@lightsofapollo.com>
Desc: Merge pull request #22944 from clouserw/patch-1

Add mkt-dev to engineering builds; bug 1011016

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https://hg.mozilla.org/integration/gaia-2_0/rev/5facd79f9ccd
Author: Wil Clouser <clouserw@gmail.com>
Desc: Add mkt-dev to engineering builds; bug 1011016
Bumping manifests a=b2g-bump