Added copyright notice

Author: aosingh

dbt/include/oracle/macros/columns.sql

@@ -1,3 +1,19 @@
+{#
+ Copyright (c) 2022, Oracle and/or its affiliates.
+ Copyright (c) 2020, Vitor Avancini
+
+  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.
+#}
 {% macro oracle__alter_relation_add_remove_columns(relation, add_columns, remove_columns) %}
 
   {% if add_columns is none %}