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

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https://hg.mozilla.org/integration/gaia-central/rev/6b344043dfb5
Author: Trif Andrei-Alin <trifandreialin@gmail.com>
Desc: Merge pull request #15275 from bobsilverberg/tbpl_calendar_tests

Bug 957122 - Enable more TBPL tests - Calendar tests

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https://hg.mozilla.org/integration/gaia-central/rev/3be3dbaa20fb
Author: Bob Silverberg <bob.silverberg@gmail.com>
Desc: Bug 957122 - Enable more TBPL tests - Calendar tests

Add test_calendar_flick_through_months and re-enable test_calendar_new_event_appears_on_all_calendar_views