[CA PoC] Add the click_house gem to GitLab

Why are we doing this work

Based on the audit we need to add a HTTP client that can talk to a ClickHouse database.

Implementation plan

Ideally, we should be able to use the click_house gem after we fork it in our group. Let's add the Gem to the Gemfile and define some basic configuration.

Validation: The application should boot with and without running ClickHouse server without any issues.

If there is something config-related, we could add test cases however, actually testing the connection and the queries will happen in a follow-up issue: #414588 (closed)