Context:
See Backend senate discussion:

https://confluence.camunda.com/display/CO/2021-08-27+Backend+Senate?focusedTaskId=10

We currently have two getters when we need the indexNamingService in our IT: one in EmbeddedOptimizeExtension and one in ElasticSearchIntegrationTestExtension.

If possible, lets remove the one in ElasticSearchIntegrationTestExtension and migrate all usages to the EmbeddedOptimizeExtension  one instead.

AT:

• IndexNamingService is removed from ElasticSearchIntegrationTestExtension **