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

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https://hg.mozilla.org/integration/gaia-central/rev/921a8c7dd926
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #21080 from KevinGrandon/bug_1030713_search_subdomain_dedupe

Bug 1030713 - [Collection app] Web results get wrongfully deduped

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https://hg.mozilla.org/integration/gaia-central/rev/7b82d0d8dbb9
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1030713 - [Collection app] Web results get wrongfully deduped r=ranbena
Bumping manifests a=b2g-bump