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

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https://hg.mozilla.org/integration/gaia-central/rev/a508cdce0830
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #19781 from guilherme-pg/bug1017741-fmd-temp-alias

Bug 1017741 - Update Find My Device's API URL to the temporary alias.

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https://hg.mozilla.org/integration/gaia-central/rev/b9e79f88d85a
Author: Guilherme Goncalves <guilherme.p.gonc@gmail.com>
Desc: Bug 1017741 - Update Find My Device's API URL to the temporary alias.
Bumping manifests a=b2g-bump