Removed final from TestStep for easier mocking

Signed-off-by: Christian Weyermann <c.weyermann@peak-solution.de>
diff --git a/src/main/java/org/eclipse/mdm/api/base/model/TestStep.java b/src/main/java/org/eclipse/mdm/api/base/model/TestStep.java
index e9af27e..fe47754 100644
--- a/src/main/java/org/eclipse/mdm/api/base/model/TestStep.java
+++ b/src/main/java/org/eclipse/mdm/api/base/model/TestStep.java
@@ -25,7 +25,7 @@
  * @author Viktor Stoehr, Gigatronik Ingolstadt GmbH
  * @author Sebastian Dirsch, Gigatronik Ingolstadt GmbH
  */
-public final class TestStep extends BaseEntity implements ContextDescribable, Datable, Deletable, Describable,
+public class TestStep extends BaseEntity implements ContextDescribable, Datable, Deletable, Describable,
 FilesAttachable, Sortable, StatusAttachable, Tagable {
 
 	// ======================================================================