Merge branch 'stable-3.0' into stable-3.1

* stable-3.0:
  Update git submodules
  Update git submodules
  Update git submodules
  Rely on a released version of gatling-git in stable branch
  ElasticVersionTest: Use latest V6 in V7 assertions
  ElasticContainer: Upgrade V6_8 to elasticsearch 6.8.12
  e2e-tests: Add presentation links to documentation

Change-Id: I44324407e0f944bc9d752c3cd4890b01bd4e7d59
tree: 5fb931283e669fff2fd35db01b37699f1c7a0848
  1. java/
  2. javatests/