Upgrade JUnit depedency to 5.4.0 (closes #402)
Upgrade JUnit depedency to 5.4.0 (closes #402)

Upgrade the JUnit dependency to the latest available 5.4.0.

Note that JUnit simplified its artifacts, and now it contains a
single, simple org.junit:junit-jupiter artifact.

MarkDacek/commons-lang,apache/commons-lang,britter/commons-lang,MarkDacek/commons-lang,MarkDacek/commons-lang,apache/commons-lang,britter/commons-lang,apache/commons-lang,britter/commons-lang