Bumping gaia.json for 4 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/5197e3219b93
Author: vingtetun <21@vingtetun.org>
Desc: Merge pull request #14014 from vingtetun/bug942716.landing

Bug 942716 - Add a developer menu in the system app. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/6f3f74c3fd12
Author: Vivien Nicolas <21@vingtetun.org>
Desc: Bug 942716 - Add a developer menu in the system app. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/9656d9afa3d0
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #14003 from askeing/942733

Bug 942733 - Xfail test_cost_control_ftu.py, test_cost_control_data_aler...

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https://hg.mozilla.org/integration/gaia-central/rev/fffae0cee261
Author: askeing <askeing@gmail.com>
Desc: Bug 942733 - Xfail test_cost_control_ftu.py, test_cost_control_data_alert_mobile.py, and test_cost_control_reset_wifi.py