Draft: Connect overage modal to account

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Related to #363498 (closed)

ee/config/feature_flags/development/show_overage_on_role_promotion.yml

@@ -2,7 +2,7 @@
 name: show_overage_on_role_promotion
 introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/89180/
 rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/199893
-milestone: '15.2'
+milestone: '15.7'
 type: development
 group: group::billing and subscription management
 default_enabled: false