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

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https://hg.mozilla.org/integration/gaia-central/rev/55a28af01d44
Author: Francisco Jordano <arcturus@ardeenelinfierno.com>
Desc: Merge pull request #11425 from comoyo/mozContacts2vcard

Bug 896982: Design and implement a component to transform mozContacts to VCARD format [r=arcturus]

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https://hg.mozilla.org/integration/gaia-central/rev/d409de36cf9f
Author: Sergi Mansilla <sergi.mansilla@gmail.com>
Desc: Design and implement a component to transform mozContacts to VCARD format