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

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https://hg.mozilla.org/integration/gaia-central/rev/a4f4c0398c18
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #12432 from jmcanterafonseca/bug-919967

Bug 919967 - Enable import contact when illegal SIM insert.

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https://hg.mozilla.org/integration/gaia-central/rev/3f070c83213a
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Bug 919967 - Enable import contact when illegal SIM insert.