Fix billing layout with upstream changes

What does this MR do and why?

Failed job: https://jihulab.com/gitlab-cn/gitlab/-/jobs/11570018

2 examples, 2 failures
Failed examples:
rspec ./ee/spec/features/billings/billing_plans_spec.rb:411 # Billing plan pages group billing page when a group is the top-level group on ultimate displays plan header
rspec ./ee/spec/features/billings/billing_plans_spec.rb:436 # Billing plan pages group billing page when a group is the top-level group on bronze displays plan header

Changes from Upstream MR: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/136482/diffs#4b6568ccd424c62247d225dfc227b4b66cbe6569

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