bump elasticsearch to version 7.7.0
<description>Oak Elasticsearch integration subproject</description>
<properties>
- <elasticsearch.version>7.6.0</elasticsearch.version>
- <lucene.version>8.4.0</lucene.version>
+ <elasticsearch.version>7.7.0</elasticsearch.version>
+ <lucene.version>8.5.1</lucene.version>
</properties>
<build>
