fix: cmek verify fixes

- ignore method additions to protobufs, external users dont implement them
- add missing copyright header

Change-Id: I2330400c144ce80e05ff1af3e5dc031f8a21aa37

google-cloud-bigtable/src/test/java/com/google/cloud/bigtable/admin/v2/it/BigtableCmekIT.java

@@ -1,3 +1,18 @@
+/*
+ * Copyright 2020 Google LLC
+ *
+ * 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
+ *
+ *     https://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 com.google.cloud.bigtable.admin.v2.it;
 
 import static com.google.common.truth.Truth.assertThat;
@@ -33,8 +48,6 @@
 
 @RunWith(JUnit4.class)
 public class BigtableCmekIT {
-  private static Logger LOG = Logger.getLogger(BigtableCmekIT.class.getName());
-
   private static final String CMEK_KMS_KEY_PROPERTY_NAME = "bigtable.kms_key_name";
 
   @ClassRule public static TestEnvRule testEnvRule = new TestEnvRule();

proto-google-cloud-bigtable-admin-v2/clirr-ignored-differences.xml

@@ -1,9 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- see http://www.mojohaus.org/clirr-maven-plugin/examples/ignored-differences.html -->
 <differences>
+    <!-- Adding method to interfaces is safe for autogenerated protobufs -->
     <difference>
         <differenceType>7012</differenceType>
-        <className>com/google/bigtable/admin/v2/TableOrBuilder</className>
-        <method>*Restore*</method>
+        <className>**</className>
+        <method>*</method>
     </difference>
 </differences>

proto-google-cloud-bigtable-v2/clirr-ignored-differences.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- see http://www.mojohaus.org/clirr-maven-plugin/examples/ignored-differences.html -->
+<differences>
+    <!-- Adding method to interfaces is safe for autogenerated protobufs -->
+    <difference>
+        <differenceType>7012</differenceType>
+        <className>**</className>
+        <method>*</method>
+    </difference>
+</differences>