修正私募查找同类基金，无满足条件却报错问题。

src/main/java/com/tanpu/fund/service/impl/ProductServiceImpl.java

@@ -1660,6 +1660,9 @@ public class ProductServiceImpl implements ProductService, Constant {
     public List<FundSameResp> querySamefund(String fundId) {
         //查询同类基金
         FundInfo fundInfo = fundInfoMapper.selectByPrimaryKey(fundId);
+        if (fundInfo == null || fundInfo.getSubstrategy() == null) {
+            return Collections.emptyList();
+        }
 
         PageMethod.startPage(1, 10);
         FundCountExample example = new FundCountExample();