Update enforcement banner to include offer details

What does this MR do and why?

It updates the enforcement banner for free namespaces to include an offer details, as described in #420779.

Screenshots or screen recordings

Before	After

How to set up and validate locally

First, Apply the patch (e.g. copy the patch then run pbpaste | git apply -):

diff --git a/ee/app/components/namespaces/free_user_cap/enforcement_at_limit_alert_component.rb b/ee/app/components/namespaces/free_user_cap/enforcement_at_limit_alert_component.rb
index 91fea9efa276..946d24b73f16 100644
--- a/ee/app/components/namespaces/free_user_cap/enforcement_at_limit_alert_component.rb
+++ b/ee/app/components/namespaces/free_user_cap/enforcement_at_limit_alert_component.rb
@@ -10,7 +10,8 @@ class EnforcementAtLimitAlertComponent < BaseAlertComponent
       OFFER_AVAILABILITY_URL = 'https://about.gitlab.com/pricing/faq-efficient-free-tier/#q-is-this-offer-available-for-all-free-tier-users'
 
       def breached_cap_limit?
-        ::Namespaces::FreeUserCap::Enforcement.new(namespace).at_limit?
+        true
+        #::Namespaces::FreeUserCap::Enforcement.new(namespace).at_limit?
       end
 
       def feature_name

1. Navigate to a free group
2. Refresh the page and observe the banner

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 #420779