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

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https://hg.mozilla.org/integration/gaia-central/rev/133429d9c01b
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #13718 from bobsilverberg/fix_dnt

Bug 938707 - Fix failure of test_settings_do_not_track

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https://hg.mozilla.org/integration/gaia-central/rev/12d522d30ff0
Author: Bob Silverberg <bob.silverberg@gmail.com>
Desc: Bug 938707 - Fix failure of test_settings_do_not_track