Do not add Elasticsearch license to new files. (#178)

Signed-off-by: Daniel (dB.) Doubrovkine <dblock@amazon.com>

config/checkstyle/checkstyle_suppressions.xml

@@ -41,5 +41,4 @@
     <suppress files="client[/\\]src[/\\]main[/\\]java[/\\]org[/\\]opensearch[/\\]client[/\\]opensearch[^.]*\.java" checks="UnusedImports" />
     <suppress files="client[/\\]src[/\\]main[/\\]java[/\\]org[/\\]opensearch[/\\]client[/\\]opensearch[/\\]OpenSearch[^.]*\.java" checks="LineLength" />
     <suppress files="client[/\\]src[/\\]main[/\\]java[/\\]org[/\\]opensearch[/\\]client[/\\]opensearch[/\\]OpenSearch[^.]*\.java" checks="UnusedImports" />
-    <suppress files="client[/\\]src[/\\]test[/\\]java[/\\]org[/\\]opensearch[/\\]client[/\\]opensearch[/\\]integTest[^.]*\.java" checks="Header" />
 </suppressions>

config/checkstyle/header.java.txt

@@ -5,27 +5,3 @@
  * this file be licensed under the Apache-2.0 license or a
  * compatible open source license.
  */
-
-/*
- * Licensed to Elasticsearch B.V. under one or more contributor
- * license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright
- * ownership. Elasticsearch B.V. licenses this file to you 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.
- */
-
-/*
- * Modifications Copyright OpenSearch Contributors. See
- * GitHub history for details.
- */