CS Add-on: Connect with Sales CTA - Usage Quotas

What does this MR do and why?

Replace the Contact sales cta with the hand raise lead button that upon click shows the contact sales modal. This is behind a shared feature flag cs_connect_with_sales.

Screenshots or screen recordings

	Before	After
Code suggestion intro
Clinking cta	Redirect to https://about.gitlab.com/sales

How to set up and validate locally

note submitting the form will fail due to CustomersDot setup. Verification of that submission can be seen in ee/spec/features/groups/usage_quotas/code_suggestions_usage_tab_spec.rb and will be verified fully in staging.

1. Setup to simulate SaaS and restart GDK
2. Enable cs_connect_with_sales and check_namespace_plan in rails console
   • Feature.enable(:cs_connect_with_sales)
   • ApplicationSetting.first.update(check_namespace_plan: true)
   • it looks like we need another FF enabled to see the tab (enable_hamilton_in_usage_quotas_ui) (added by @ohoral)
3. Create a new top-level group.
4. Apply the premium plan to the group via rails console

group = Group.last
plan = Plan.find_by(name: 'premium')
group.gitlab_subscription.update(hosted_plan: plan)

1. Verify usage_quotas page code_suggestions tab (example: gdk.test:3000/groups/test-pql/-/usage_quotas#code-suggestions-usage-tab)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #421952 (closed)