[MPMD-247] Upgrade to PMD 6.0.0

Remove rule EmptyStaticInitializer from default ruleset, since
it has been merged into EmptyInitializer
1 file changed
tree: cbe5384e67edaafdc8cc5d333a5091e670cf9c85
  1. src/
  2. .gitignore
  3. Jenkinsfile
  4. pom.xml