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

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https://hg.mozilla.org/integration/gaia-central/rev/a76c9fafd160
Author: Fabien Cazenave <fabien@cazenave.cc>
Desc: Merge pull request #14044 from fabi1cazenave/fdnActionMenu-bug928621

Bug 928621 - Make call-fdnAction-menu hidden by default, r=arthur

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https://hg.mozilla.org/integration/gaia-central/rev/5a4a4aedc77f
Author: Fabien Cazenave <fabien@cazenave.cc>
Desc: Bug 928621 - Make call-fdnAction-menu hidden by default
moving the action menu to the `FDN list` panel