Add tests for lazy quantifier inside optional group

[stephentoub]

Add test cases for the pattern a(b.*?c)?d to confirm the fix from #124254 addresses the regression reported in #125321, where a lazy quantifier inside an optional group incorrectly failed to match.

Tests cover:

• Lazy must expand: abccd — lazy .*? must grow past first c for d to match
• Lazy zero-width: abcd — lazy .*? matches nothing, c and d align immediately
• Optional group skipped: ad — the entire (b.*?c)? group is bypassed
• No match: abce — no d available, match correctly fails

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[Copilot]

Pull request overview

This PR adds four test cases for the regex pattern a(b.*?c)?d to the existing Match_MemberData_Cases test data provider, verifying the fix from PR #124254 for the regression reported in issue #125321 where a lazy quantifier inside an optional group incorrectly failed to match.

Changes:

• Added four yield return entries covering lazy-must-expand, lazy-zero-width, optional-group-skipped, and no-match scenarios for the a(b.*?c)?d pattern.

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