#27 -- fix long execution time of removing commits

src/main/java/ru/ulstu/extractor/service/CommitService.java

@@ -10,7 +10,6 @@ import org.springframework.stereotype.Service;
 import ru.ulstu.extractor.model.Commit;
 import ru.ulstu.extractor.repository.CommitRepository;
 
-import javax.transaction.Transactional;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -40,9 +39,8 @@ public class CommitService {
                 }).collect(Collectors.toList());
     }
 
-    @Transactional
     public void deleteWithEmptyIds() {
-        commitRepository.deleteByBranchIsNull();
+        jdbcTemplate.update("DELETE FROM commit where branch_id is null");
     }
 
     public void updateBranchId(List<Commit> commits, Integer branchId) {