ElasticVersion: Say 'Unsupported' rather than 'Invalid'

If a version number is not recognized, it is not necessarily invalid,
but could just be because we didn't yet add support for it.

Change the error message to be less aggressive.

Change-Id: I904ff165b7e04ae0c5e7514923a75f6a74e8b005
2 files changed
tree: d017b8e3482186477445310d67f0eee351b21142
  1. gerrit-acceptance-tests/
  2. gerrit-elasticsearch/
  3. gerrit-pgm/