Added missing vars in serviceapi and clusterDomain var

[ifurs]

Motivation:

• For cluserDomain I use in my workaround cluster with different DNS name, also I think many companies use different domain, so It would be useful
• I've found that in Chart is missing credentials for ES/OS in serviceapi, I've copied variables from service jobs

Referenced issue: 2255

[ifurs]

it would be great to squash commits:)

[dmakeienko]

Same issue, waiting for merge

[raikbitters]

Hello @ifurs, could you please create separate PRs for ES/OS environments and update them based on the changes made? Once done, kindly reopen this PR.