Billing page plan actions for JH
Problem to solve
The current group billing page will be upgraded to a internal modal that collects users information and send to the marketing team, but for JH we need to keep the current implementation which is when clicking the contact sales button it should be redirect to sales page, so that we can ask users to input informations for marketing cause.
Per https://gitlab.com/gitlab-org/gitlab/-/merge_requests/74494#note_734094001, this feature will be fully enabled in milestone 14.6.
For now the _billing_plan.html.haml is completely overridden by JH (see https://gitlab.com/gitlab-jh/gitlab/-/merge_requests/162), we need to remove the override file once our pricing info can go public.
After the file is restored, the feature will be inherited from EE, so we need to add a new partial page for the billing_plans so that we can keep our existing behavior (redirect to sales page) instead of inheriting the EE behavior.