ElasticContainer: Upgrade V7_8 to elasticsearch 7.8.1

Upgrade elasticsearch-rest-client to 7.8.1, accordingly.

Change-Id: I0c904bc9adaef56e01a2f584e477a6acff959cdd
1 file changed
tree: 7d65fec6f400df917b11f1a6a66bd1509a10d4a9
  1. java/
  2. javatests/