Part of #2524

Currently we use some mixture of jupiter runner and junit4 vintage engine. We should clean this up and migrate to use JUnit5 only.
This reduces the footprint of our dev libraries/dependencies.

Things to be considered:

• Support Rule Test Framework (PMDTestRunner)
• IntelliJ IDEA support (see also [test] Improve xml test schema #3302 )
• Update dev documentation
• org.junit.runners.Suite

Tasks:

• Migrate to JUnit5 - Part 1 #3945
• Migrate to JUnit5 - Part 2 #4028
• Migrate to JUnit5 - Part 3 #4155