ci(release-audit): add license header and dependency checker (#1687)

* ci(release-audit): add license header and dependency checker
* chore: add Apache license headers
* chore: add new line to .ratignore

spec/fixtures/android_studio_project/gradle/wrapper/gradle-wrapper.properties

@@ -1,3 +1,20 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF 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.
+
 #Mon Dec 28 10:00:20 PST 2015
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists