chore(package): update react-addons-test-utils to version 15.4.2
chore(package): update react-addons-test-utils to version 15.4.2

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dryna/keystone-twoje-urodziny,ONode/keystone,concoursbyappointment/keystoneRedux,vokal/keystone,benkroeger/keystone,rafmsou/keystone,concoursbyappointment/keystoneRedux,Pop-Code/keystone,andrewlinfoot/keystone,vokal/keystone,andrewlinfoot/keystone,rafmsou/keystone,matthewstyers/keystone,trentmillar/keystone,andrewlinfoot/keystone,frontyard/keystone,dryna/keystone-twoje-urodziny,naustudio/keystone,vokal/keystone,ratecity/keystone,trentmillar/keystone,matthewstyers/keystone,naustudio/keystone,frontyard/keystone,ONode/keystone,trentmillar/keystone,frontyard/keystone,danielmahon/keystone,danielmahon/keystone,danielmahon/keystone,benkroeger/keystone,Pop-Code/keystone,naustudio/keystone,matthewstyers/keystone,ratecity/keystone,benkroeger/keystone