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

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https://hg.mozilla.org/integration/gaia-central/rev/d0fb4a424eb3
Author: AndreiH <andrei.hutusoru@softvision.ro>
Desc: Merge pull request #20895 from zacc/bug_1028159

Bug 1028159 - Target intermittent failure in test_edit_contact.py

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https://hg.mozilla.org/integration/gaia-central/rev/b6a72a565f3a
Author: Zac <zcampbell@mozilla.com>
Desc: Bug 1028159 - Target intermittent failure in test_edit_contact.py
Bumping manifests a=b2g-bump