[pom] Update assertj-core to 3.8.0
[pom] Update assertj-core to 3.8.0

dblock/waffle,hazendaz/waffle,Waffle/waffle,hazendaz/waffle,dblock/waffle,Waffle/waffle,Waffle/waffle,dblock/waffle,dblock/waffle,hazendaz/waffle