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

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https://hg.mozilla.org/integration/gaia-central/rev/f307e8d1ab4f
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #14162 from askeing/944264

Bug 944264 - Xfail test_cost_control_reset_wifi.py

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https://hg.mozilla.org/integration/gaia-central/rev/4595b9fa24a8
Author: askeing <askeing@gmail.com>
Desc: Bug 944264 - Xfail test_cost_control_reset_wifi.py