Fix checkstyle issue.

#1771

Author: mmerdes

platform-tests/src/test/java/org/junit/platform/testkit/engine/EventsTests.java

@@ -10,7 +10,9 @@
 
 package org.junit.platform.testkit.engine;
 
-import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.platform.testkit.engine.EventConditions.engine;
 import static org.junit.platform.testkit.engine.EventConditions.event;
 import static org.junit.platform.testkit.engine.EventConditions.finishedSuccessfully;