Add and test examples for common values

[eliobischof]

As a user, I want to have an example for my use case, so that I can create a fast proof of concept.

Acceptance Criteria

• An example for ZITADEL with an insecure Cockroach DB is available and automatically tested
• An example for ZITADEL with a secure Cockroach DB with TLS authentication is available and automatically tested
• An example for ZITADEL with a secure Cockroach DB with password authentication is available and automatically tested
• An example for ZITADEL with an insecure Postgres DB is available and automatically tested
• An example for ZITADEL with a secure Postgres DB with TLS authentication is available and automatically tested
• An example for ZITADEL with a secure Postgres DB with password authentication is available and automatically tested

Actually, probably not all the configurations listed in the AC are working already, And it's possible that we have introduce breaking changes and release a new major version.

Related issues:

• Installation stuck at PodInitializing #56
• Unable to use helm chart with postgresql database #82

[eliobischof]

@hifabienne I think we have to estimate this one quickly, as it's probably a blocker for many users.

[eliobischof]

@stebenz do you have any opinions on the acceptance criteria?

[grobarko]

@eliobischof I believe this is not only docs issue. As it was pointed out in #82, when trying to run the helm chart with Postgres, the Job/zitadel-init fails due to the following error:

Warning  FailedMount  3s (x6 over 19s)  kubelet            MountVolume.SetUp failed for volume "db-ssl-root-crt" : secret "crdb-ca-secret" not found                          │
│   Warning  FailedMount  3s (x6 over 19s)  kubelet            MountVolume.SetUp failed for volume "db-ssl-client-crt" : secret "crdb-client-secret" not found

So please take that into account as well.