test: tst.selfarray2.d should not PASS

Due to the drop support triggering bad address faults, this test ended
up reporting XPASS which it really should not.  Added an explicit ERROR
clause to detect faults (and report failure if a fault occurs).

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Reviewed-by: Eugene Loh <eugene.loh@oracle.com>

test/unittest/scalars/tst.selfarray2.d

@@ -1,6 +1,6 @@
 /*
  * Oracle Linux DTrace.
- * Copyright (c) 2006, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2023, Oracle and/or its affiliates. All rights reserved.
  * Licensed under the Universal Permissive License v 1.0 as shown at
  * http://oss.oracle.com/licenses/upl.
  */
@@ -44,3 +44,8 @@ tick-1sec
 {
 	exit(0);
 }
+
+ERROR
+{
+	exit(1);
+}