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

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https://hg.mozilla.org/integration/gaia-central/rev/923bd215fb8f
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #11157 from jmcanterafonseca/bkelly_bug

Revert "Bug 894611: Defer contact placeholder creation during load."

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https://hg.mozilla.org/integration/gaia-central/rev/bb1a3e3264ce
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Revert "Bug 894611: Defer contact placeholder creation during load."

This reverts commit 5adb1074a9c9f6a96579174c0751516ffd38b2b5.