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

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https://hg.mozilla.org/integration/gaia-central/rev/87d4039f587f
Author: Germán Toro del Valle <gtorodelvalle@gmail.com>
Desc: Merge pull request #12621 from gtorodelvalle/contacts-bug-922083-unit-tests-for-duplicate-contact-details-reloaded

Contacts bug 922083 unit tests for duplicate contact details reloaded (r=jmcanterafonseca)

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https://hg.mozilla.org/integration/gaia-central/rev/35669903b494
Author: Germán Toro del Valle <gtorodelvalle@gmail.com>
Desc: Bug 922083 - [Contacts] Include unit tests to cover the presentation of the duplicate contact details overlay.