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

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https://hg.mozilla.org/integration/gaia-central/rev/69f220a0382b
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #10489 from jmcanterafonseca/custom_urls_services

Bug 883510 - Partner customization should be able to set Facebook OAuth ...

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https://hg.mozilla.org/integration/gaia-central/rev/660b952ff131
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Bug 883510 - Partner customization should be able to set Facebook OAuth 2 callback url completely