Fix sample projects for JUnit 5.5.x support

test-project-groovy/gradle.properties

@@ -1 +1,2 @@
-jUnitVersion = 5.3.1
+jUnitVersion = 5.6.2
+jUnitPlatformVersion = 1.6.2

test-project-kotlin/build.gradle.kts

@@ -19,6 +19,7 @@ subprojects {
     val testRuntimeOnly by configurations
 
     val jUnitVersion: String by project
+    val jUnitPlatformVersion: String by project
     //endregion
 
     //region KOTLIN
@@ -51,6 +52,7 @@ subprojects {
         testImplementation("org.junit.jupiter:junit-jupiter-api:$jUnitVersion")
         testImplementation("org.junit.jupiter:junit-jupiter-params:$jUnitVersion")
         testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:$jUnitVersion")
+        testRuntimeOnly("org.junit.platform:junit-platform-launcher:$jUnitPlatformVersion")
     }
 
 //    build.dependsOn(javadoc) // TODO: No public or protected classes found to document

test-project-kotlin/gradle.properties

@@ -1 +1,2 @@
-jUnitVersion = 5.3.1
+jUnitVersion = 5.6.2
+jUnitPlatformVersion = 1.6.2

test-project-mixed/build.gradle

@@ -26,6 +26,7 @@ subprojects {
         testImplementation "org.junit.jupiter:junit-jupiter-api:$jUnitVersion"
         testImplementation "org.junit.jupiter:junit-jupiter-params:$jUnitVersion"
         testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:$jUnitVersion"
+        testRuntimeOnly "org.junit.platform:junit-platform-launcher:$jUnitPlatformVersion"
     }
 
     build.dependsOn javadoc

test-project-mixed/gradle.properties

@@ -1 +1,2 @@
-jUnitVersion = 5.3.1
+jUnitVersion = 5.6.2
+jUnitPlatformVersion = 1.6.2

test-project/gradle.properties

@@ -1,2 +1,2 @@
-jUnitVersion = 5.5.2
-jUnitPlatformVersion = 1.5.2
+jUnitVersion = 5.6.2
+jUnitPlatformVersion = 1.6.2