Downgrade JUnit version to match Vert.x core
Downgrade JUnit version to match Vert.x core

vert-x/mod-lang-scala,galderz/mod-lang-scala,vert-x/mod-lang-scala,galderz/mod-lang-scala,galderz/mod-lang-scala,galderz/mod-lang-scala,vert-x/mod-lang-scala