m/p/verity: add a missing copyright notice

Change-Id: I330c3bf748c25b44a0616147b430b051bb8a5f99
Reviewed-on: https://review.monogon.dev/c/monogon/+/459
Reviewed-by: Sergiusz Bazanski <serge@monogon.tech>
diff --git a/metropolis/pkg/verity/encoder_test.go b/metropolis/pkg/verity/encoder_test.go
index 21c4623..c3a39fb 100644
--- a/metropolis/pkg/verity/encoder_test.go
+++ b/metropolis/pkg/verity/encoder_test.go
@@ -1,3 +1,19 @@
+// Copyright 2020 The Monogon Project Authors.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package verity
 
 import (