Created a setup and test cases for Elasticsearch testing

What does this MR do?

Adding a test case setup for Elasticsearch testing as well as page object upgrades as well as resource upgrades to enable the changing of settings through the API. By doing this, it is possible to enable Elasticsearch search and indexing using this resource class.

Corresponding CE upstream: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/30932

Closes https://gitlab.com/gitlab-org/gitlab-ee/issues/12166

Closes https://gitlab.com/gitlab-org/gitlab-ee/issues/12023

Does this MR meet the acceptance criteria?

• Code review guidelines
• Style guides
• Separation of EE specific content