Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/42747ca84e20
Author: Zac <zcampbell@mozilla.com>
Desc: Bug 985558 - Make is_wifi_enabled handle mozWifiManager states

Conflicts:
	tests/python/gaia-ui-tests/gaiatest/tests/functional/ftu/test_ftu_skip_tour.py
Bumping manifests a=b2g-bump