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

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https://hg.mozilla.org/integration/gaia-central/rev/fee731772272
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #16596 from crh0716/968681

Bug 968681 - Add marionette tests for the display panel r=evanxd

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https://hg.mozilla.org/integration/gaia-central/rev/0dfd762a9ec9
Author: Arthur Chen <crh0716@gmail.com>
Desc: Bug 968681 - Add marionette tests for the display panel
Bumping manifests a=b2g-bump