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

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https://hg.mozilla.org/integration/gaia-central/rev/fce247ce7551
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #20311 from guilherme-pg/bug1017748-fmd-oauth-url

Bug 1017748 - Use FxA's OAuth URL in Find My Device.

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https://hg.mozilla.org/integration/gaia-central/rev/ee6495fafa45
Author: Guilherme Goncalves <guilherme.p.gonc@gmail.com>
Desc: Bug 1017748 - Use FxA's OAuth URL in Find My Device.
Bumping manifests a=b2g-bump