fix: update file limit binding in LocalFileUpload component

--bug=1064093 --user=刘瑞斌 【工作流知识库】本地文件数据源节点，设置每次最多上传文件数限制无效 https://www.tapd.cn/62980211/s/1806155

Author: liuruibin

ui/src/components/dynamics-form/items/upload/LocalFileUpload.vue

@@ -10,7 +10,7 @@
       :auto-upload="false"
       :show-file-list="false"
       :accept="accept"
-      :limit="attrs.limit"
+      :limit="file_count_limit"
       :on-exceed="onExceed"
       :on-change="fileHandleChange"
       @click.prevent="handlePreview(false)"
@@ -75,7 +75,7 @@ const props = withDefaults(defineProps<{ modelValue?: any; formField: FormField
 const onExceed = () => {
   MsgError(
     t('views.document.tip.fileLimitCountTip1') +
-      attrs.limit +
+      file_count_limit.value +
       t('views.document.tip.fileLimitCountTip2'),
   )
 }