fix(funnel-breakdown): bad link

[EDsCODE]

Problem

• addresses Persons modal scoped when it shouldn't when in funnel breakdown #10691
• the link wasn't using the "baseline" link when a breakdown was active
• this ensures that if there's a breakdown, the first element of the nested_breakdown group is used which is "baseline"

Changes

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How did you test this code?

[posthog-bot]

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