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

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https://hg.mozilla.org/integration/gaia-central/rev/3985c617f2bb
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #18687 from bebef1987/settings

Bug 1000062 - Delete some more redundant tests

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https://hg.mozilla.org/integration/gaia-central/rev/54b613a912e8
Author: Bebe <bebe@mozilla.ro>
Desc: Bug 1000062 - Delete some more redundant tests

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https://hg.mozilla.org/integration/gaia-central/rev/1f95c8348db3
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #18713 from KevinGrandon/bug_1001888_jshint_shared_test_unit

Bug 1001888 - JSHint fixes for shared/js/test/unit

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https://hg.mozilla.org/integration/gaia-central/rev/4fa9e7e125b1
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1001888 - JSHint fixes for shared/js/test/unit r=etienne
Bumping manifests a=b2g-bump