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/511fbe935904
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #14163 from jmcanterafonseca/fix_import_export_flows

Bug 943298 - In SIM import-export contacts flows avoid creating new entr...

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https://hg.mozilla.org/integration/gaia-1_2/rev/d38de90e767b
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Bug 943298 - In SIM import-export contacts flows avoid creating new entries in the SIM card