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

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https://hg.mozilla.org/integration/gaia-central/rev/e66736fa0017
Author: Anthony Ricaud <anthony@ricaud.me>
Desc: Merge pull request #14006 from evanxd/bug-942490

Bug 942490 - [integraion-test] The media_playback_test test is failed in local and Travis. r=rik

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https://hg.mozilla.org/integration/gaia-central/rev/19bd8012006a
Author: Evan Xd <itoyxd@gmail.com>
Desc: Bug 942490 - Disable the reopening music app test.