8254748: Bad Copyright header format after JDK-8212218

Reviewed-by: shade, dholmes

test/hotspot/jtreg/runtime/ErrorHandling/TestHeapDumpOnOutOfMemoryError.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it