Improve info on Free Public Namespaces

What does this MR do and why?

Related to #429828 (closed). This is a part in a series of MRs (see more info here):

Description	MR
Augment updateSubscriptionPlanApolloCache	!137552 (merged)
Improve info on Free Public Namespaces	👈 you are here

In this MR, we are creating the new component PublicNamespacePlanInfoCard. Its purpose is to show info for Public Namespaces (e.g., Free, Paid, and OSS program related). However, given the related Issue has been deprioritised and scheduled for later, with this iteration, the PublicNamespacePlanInfoCard will only show info for Public Free Namespaces.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Before	After

How to set up and validate locally

• Needs gdk and CustomersDot (also staging)
• Create a Free Public Namespace
• visti groups/<your-group-name>/-/usage_quotas#seats-quota-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.