ElasticReindexIT: Add tests against Elasticsearch version 6

Bug: Issue 9112
Change-Id: I04f275dd930308d610320dcd072522d018535157
1 file changed
tree: d8b84bd8154ccb56c21bb71ece97f11e65cb9793
  1. gerrit-acceptance-tests/
  2. gerrit-elasticsearch/
  3. gerrit-pgm/