Elasticsearch: Ensure request URI is always prefixed with "/"

When using Amazon's Elasticsearch service, requests fail with "400 Bad
Request" if they are not prefixed with "/".

Ensure that requests are always prefixed with "/".

Bug: Issue 9761
Change-Id: If2a178e85143ba75d7f4f6b982739a9b3f2dc21c
3 files changed
tree: 9aed404d74abe82c4aa49517496f1a4215f152d4
  1. gerrit-acceptance-tests/
  2. gerrit-elasticsearch/
  3. gerrit-pgm/