fix(用例管理): 修复文件上传为路径时更新和复制报错问题

--bug=1036311 --user=郭雨琦 https://www.tapd.cn/55049933/bugtrace/bugs/view/1155049933001036311

backend/services/case-management/src/main/java/io/metersphere/functional/service/FunctionalCaseAttachmentService.java

@@ -381,7 +381,7 @@ public class FunctionalCaseAttachmentService {
         functionalCaseAttachmentExample.createCriteria().andCaseIdEqualTo(caseId).andFileIdIn(uploadFileIds).andFileSourceEqualTo(fileSource);
         List<FunctionalCaseAttachment> existFiles = functionalCaseAttachmentMapper.selectByExample(functionalCaseAttachmentExample);
         List<String> existFileIds = existFiles.stream().map(FunctionalCaseAttachment::getFileId).distinct().toList();
-        List<String> filIds = uploadFileIds.stream().filter(t -> !existFileIds.contains(t)).toList();
+        List<String> filIds = uploadFileIds.stream().filter(t -> !existFileIds.contains(t) && StringUtils.isNotBlank(t)).toList();
         if (CollectionUtils.isEmpty(filIds)) {
             return;
         }