The flex-list refactor (#37505) raised the shared `.item-trailing`
selector's specificity, so its `flex-wrap: wrap` started overriding the
run list's intended `flex-wrap: nowrap` — a long branch name pushed the
trailing content past its fixed 280px width and wrapped the kebab menu
onto its own line.
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>