add comma

Author: Vladimir Kotal

plugins/src/test/java/opengrok/auth/plugin/UserWhiteListPluginTest.java

@@ -19,7 +19,7 @@
 
 /*
  * Copyright (c) 2020, Chris Fraire <[email protected]>.
- * Copyright (c) 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
  */
 package opengrok.auth.plugin;