fix: 关闭sqlSession前判空 (#12538)

Co-authored-by: shiziyuan9527 <yuhao.li@fit2cloud.com>

backend/src/main/java/io/metersphere/track/service/TestPlanReportService.java

@@ -920,8 +920,10 @@ public class TestPlanReportService {
                 sqlSession.flushStatements();
             }
         } finally {
+            if (sqlSession != null && sqlSessionFactory != null) {
                 SqlSessionUtils.closeSqlSession(sqlSession, sqlSessionFactory);
             }
+        }
 
     }