Disable group runners dashboard when ClickHouse is not configured

What does this MR do and why?

This change adds a new panel in the group runners dashboard to shows the usage of compute minutes by runner and project.

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

ClickHouse disabled	ClickHouse Enabled

How to set up and validate locally

1. Ensure you have a GitLab enterprise license
2. Visit any group you own -> Runners

If you haven't configured ClickHouse locally

1. Check you don't see a Fleet Dashboard link
2. Locally open config/click_house.yml and configure it (according to https://docs.gitlab.com/ee/development/database/clickhouse/clickhouse_within_gitlab.html).
3. Locally I used the following config/click_house.yml file:

test:
  main:
    database: gitlab_clickhouse_test
    url: 'http://localhost:8123'
    username: default
development:
  main:
    database: gitlab_clickhouse_development
    url: 'http://localhost:8123'
    username: default

1. Restart GDK
2. Refresh any group you own -> Runners
3. Check you see a Fleet Dashboard link and can visit the dashboard (e.g. /groups/flightjs/-/runners/dashboard).

If you have configured ClickHouse locally

1. Open config/click_house.yml and remove its contents
2. Restart rails-web: gdk restart rails-web
3. Refresh any group you own -> Runners
4. Check you don't see a Fleet Dashboard link
5. Follow the steps in the section above

Related to #459052 (closed)