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

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https://hg.mozilla.org/integration/gaia-central/rev/c8a6d1f1730e
Author: Sherman Chen <shamenchens@users.noreply.github.com>
Desc: Merge pull request #22920 from shamenchens/Bug1053728-RocketBarSearch

Bug 1053728 - App icon size incorrect from rocket bar search result, r=kgrandon

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https://hg.mozilla.org/integration/gaia-central/rev/547d89c46f98
Author: Sherman Chen <shamen.chens@gmail.com>
Desc: Bug 1053728 - App icon size incorrect from rocket bar search result
Bumping manifests a=b2g-bump