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

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https://hg.mozilla.org/integration/gaia-central/rev/f20dec34d376
Author: Carsten Book <tomcat@mozilla.com>
Desc: Merge pull request #23795 from mancas/bug1064156

Bug 1064156 - Add unit test for bug 824131 - Wifi wrong password notific... r=arthur.chen

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https://hg.mozilla.org/integration/gaia-central/rev/453415fad5cb
Author: Manuel Casas Barrado <manuel.casasbarrado@telefonica.com>
Desc: Bug 1064156 - Add unit test for bug 824131 - Wifi wrong password notification
Bumping manifests a=b2g-bump