Remove unused import

Author: Sanne

hibernate-reactive-core/src/test/java/org/hibernate/reactive/EmptyCompositeCollectionKeyTest.java

@@ -18,7 +18,6 @@
 import org.hibernate.Hibernate;
 import org.hibernate.cfg.Configuration;
 import org.hibernate.cfg.Environment;
-import org.hibernate.reactive.containers.DatabaseConfiguration;
 import org.hibernate.reactive.testing.DatabaseSelectionRule;
 
 import org.junit.Rule;