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

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https://hg.mozilla.org/integration/gaia-central/rev/3a9c5152b8c7
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #25577 from alivedise/bugzilla/1090163/core-instantiation-support

Bug 1090163 - Support normal stage 1 instantiation in core, r=timdream

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https://hg.mozilla.org/integration/gaia-central/rev/e4e62194528d
Author: Alive Kuo <alegnadise@gmail.com>
Desc: Bug 1090163 - Support normal stage 1 instantiation in core
Bumping manifests a=b2g-bump