Style mismatch for compound expandable rows between light and dark modes

[katarinazaprazna]

Actual Behaviour

There is a visual discrepancy in how compound expandable rows are rendered in light and dark mode

Expected Behaviour

The compound expandable rows should maintain a consistent design language in both light and dark modes

Screenshots

The border around the expandable row content is missing in dark mode:

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Jira Issue: PF-4336