Upgrade to JUnit 5.5.0

Author: garyrussell

build.gradle

@@ -88,8 +88,8 @@ subprojects { subproject ->
 		jackson2Version = '2.9.9'
 		jaywayJsonPathVersion = '2.4.0'
 		junit4Version = '4.12'
-		junitJupiterVersion = '5.4.0'
-		junitPlatformVersion = '1.4.0'
+		junitJupiterVersion = '5.5.0'
+		junitPlatformVersion = '1.5.0'
 		log4jVersion = '2.11.2'
 		logbackVersion = '1.2.3'
 		mockitoVersion = '2.28.2'