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

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https://hg.mozilla.org/integration/gaia-central/rev/65b86877ca39
Author: Mason Chang <mason@masonchang.com>
Desc: Merge pull request #15164 from changm/bug957913

Bug 957913 Async Load submodules of connectivity. r+ :kaze

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https://hg.mozilla.org/integration/gaia-central/rev/7944fd7e464e
Author: Mason Chang <mchang@mozilla.com>
Desc: Bug 957913 Async Load submodules of connectivity
Bug 958250 - Improve lazy loading in TelemetryPing.js r=nfroyd