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

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https://hg.mozilla.org/integration/gaia-central/rev/f81cbb09b46b
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #16563 from julienw/land-964725

Bug 964725 - [Messages] Support ',' as a recipient delimiter r=julienw

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https://hg.mozilla.org/integration/gaia-central/rev/436716555b24
Author: sasikala.paruchuri <sasikala.paruchuri@lge.com>
Desc: Bug 964725 - [Messages] Support ',' as a recipient delimiter r=julienw
Bumping manifests a=b2g-bump