[pom] Upgrade findbugs-maven-plugin to 3.0.4
[pom] Upgrade findbugs-maven-plugin to 3.0.4

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