Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/9c3601451ce3
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Revert "Merge pull request #18302 from zbraniecki/995425-upgrade-sinon"

This reverts commit 9869eaa311e54248140731955496d44d1f578943, reversing
changes made to 7591e9dc782ac2e97d63a96f9deb71c7b3588328.
Bumping manifests a=b2g-bump