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

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https://hg.mozilla.org/integration/gaia-central/rev/cfca676ee9f9
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #25917 from alivedise/bugzilla/1091739/unwrap-promise

Bug 1091379 - Proxy promise request in system service, r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/5763ef019b52
Author: Alive Kuo <alegnadise@gmail.com>
Desc: Bug 1091379 - Proxy promise request in system service
Bumping manifests a=b2g-bump