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

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https://hg.mozilla.org/integration/gaia-central/rev/81b9711ad71e
Author: Germán Toro del Valle <gtorodelvalle@gmail.com>
Desc: Merge pull request #12612 from gtorodelvalle/contacts-bug-922711-matching-email-addresses-not-highlighted

Contacts bug 922711 matching email addresses not highlighted

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https://hg.mozilla.org/integration/gaia-central/rev/4eaa05a3866f
Author: Germán Toro del Valle <gtorodelvalle@gmail.com>
Desc: Bug 922711 - [Contacts] Matching contacts email addresses are not highlighted in the matching details overlay.