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

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https://hg.mozilla.org/integration/gaia-central/rev/78b5e036130a
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #15215 from KevinGrandon/bug_958725_search_app_launch

Bug 958725 - [Search] Apps are not launching when tapped on

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https://hg.mozilla.org/integration/gaia-central/rev/c767794752c9
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 958725 - [Search] Apps are not launching when tapped on