Adds Testcontainers with SSL config for SSL-specific testing

[damccorm]

Some features of the ElasticsearchIO connector[1] can only be verified by testing against a cluster with SSL and user/password authentication enabled.  We should provide a way to test that kind of environment specifically, ideally using Testcontainers (possibly along with docker-compose?).

 

[1] https://github.com/apache/beam/pull/17297#discussion_r857612803

Imported from Jira BEAM-14531. Original Jira may contain additional context. Reported by: egalpin.

[johnjcasey]

@egalpin @nishantjain91 are either of you planning to work on these test cases?

[nishantjain91]

@johnjcasey loved to work on this but can only start in next month

[johnjcasey]

Np, that timeline is fine. I'll assign this to you, and we can remove awaiting triage from this