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

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https://hg.mozilla.org/integration/gaia-central/rev/559f40878cb1
Author: Ben Francis <ben@tola.me.uk>
Desc: Merge pull request #24383 from benfrancis/1060577

Bug 1060577 - Adjust Rocketbar backdrop opacity on input r=kgrandon

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https://hg.mozilla.org/integration/gaia-central/rev/86fd1bad48ee
Author: Ben Francis <ben@tola.me.uk>
Desc: Bug 1060577 - Adjust Rocketbar backdrop opacity when displaying results
Bumping manifests a=b2g-bump