org.junit.platform.testkit is not compatible with latest version of AssertJ

Junit Platform 1.7.1, AssertJ 3.19.0 ->

```
java.lang.NoSuchMethodError: org.assertj.core.api.SoftAssertions.fail(Ljava/lang/String;)V

	at org.junit.platform.testkit.engine.Events.checkCondition(Events.java:455)
	at org.junit.platform.testkit.engine.Events.assertEventsMatchLoosely(Events.java:420)
	at org.junit.platform.testkit.engine.Events.assertEventsMatchLoosely(Events.java:301)
```