Generic/ByteOrderMark: add UTF-16 BOM character tests

Author: rodrigoprimo

src/Standards/Generic/Tests/Files/ByteOrderMarkUnitTest.1.inc

@@ -1,4 +1,4 @@
 <?php
-// File with a byte order mark (BOM) character before the opening PHP tag.
+// File with a UTF-8 byte order mark (BOM) character before the opening PHP tag.
 echo 'foo';
 ?>