Update copyright date on new files.
diff --git a/compiler/back_end/cpp/testcode/importer2_test.cc b/compiler/back_end/cpp/testcode/importer2_test.cc
index 100435d..15a24aa 100644
--- a/compiler/back_end/cpp/testcode/importer2_test.cc
+++ b/compiler/back_end/cpp/testcode/importer2_test.cc
@@ -1,4 +1,4 @@
-// Copyright 2019 Google LLC
+// Copyright 2023 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
diff --git a/testdata/importer2.emb b/testdata/importer2.emb
index 5d9c769..0732c22 100644
--- a/testdata/importer2.emb
+++ b/testdata/importer2.emb
@@ -1,4 +1,4 @@
-# Copyright 2019 Google LLC
+# Copyright 2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.