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

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https://hg.mozilla.org/integration/gaia-central/rev/dd788ef126f8
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #24141 from julienw/1035133-test-agent-warning

Bug 1035133 - [TestAgent] Check that the TestAgent object is here and di...+shepherd

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https://hg.mozilla.org/integration/gaia-central/rev/64c0b02b4a6a
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 1035133 - [TestAgent] Check that the TestAgent object is here and display an error message otherwise r=yurenju r=rickychien
Bumping manifests a=b2g-bump