Bumping gaia.json for 2 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/a3d07c407326
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #14568 from jmcanterafonseca/fix_dups_export_bug948862_v12

Bug 948862 - [Contacts] The first time exporting a contact to SIM create...

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https://hg.mozilla.org/integration/gaia-1_2/rev/12d04f271962
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Bug 948862 - [Contacts] The first time exporting a contact to SIM creates a duplicate of the contact in the contact list