Tweak excludes and add missing copyrights

Author: eregon

src/main/ruby/truffleruby/core/data.rb

@@ -1,5 +1,13 @@
 # frozen_string_literal: true
 
+# Copyright (c) 2025 Oracle and/or its affiliates. All rights reserved. This
+# code is released under a tri EPL/GPL/LGPL license. You can use it,
+# redistribute it and/or modify it under the terms of the:
+#
+# Eclipse Public License version 2.0, or
+# GNU General Public License version 2, or
+# GNU Lesser General Public License version 2.1.
+
 module Truffle
   module DataOperations
     def self.unknown_keywords_message(given, object)

tool/update_copyright.rb

@@ -90,6 +90,7 @@
   src/main/c/io-console
   src/main/c/nkf
   src/main/c/openssl
+  src/main/c/prism-gem
   src/main/c/psych
   src/main/c/rbconfig-sizeof
   src/main/c/ripper