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

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https://hg.mozilla.org/integration/gaia-central/rev/4c132bf7d07d
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #23476 from crdlc/bug-1031084-v2

Bug 1031084 - Save to homescreen is still displayed even though this app...

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https://hg.mozilla.org/integration/gaia-central/rev/476312af2c50
Author: crdlc <crdlc@tid.es>
Desc: Bug 1031084 - Save to homescreen is still displayed even though this app is already on the homescreen
Bumping manifests a=b2g-bump