Fix unused-result warning in lastIndexOf() call
[[nodiscard]] is arguably wrong for the lastIndexOf() that takes an optional pointer to a QRegularExpressionMatch, because we can inspect that object to see if we had a match.
[[nodiscard]] is arguably wrong for the lastIndexOf() that takes an optional pointer to a QRegularExpressionMatch, because we can inspect that object to see if we had a match.