fix: fix bug with render class ant-upload-drag-container in dom (#6413)

Co-authored-by: Dmytro Lukashenko <dmytro.lukashenko@levi9.com>

Author: Dmytro-Lukashenko

components/upload/Upload.tsx

@@ -394,7 +394,7 @@ export default defineComponent({
                 class={`${prefixCls.value}-btn`}
                 v-slots={slots}
               >
-                <div class={`${prefixCls}-drag-container`}>{slots.default?.()}</div>
+                <div class={`${prefixCls.value}-drag-container`}>{slots.default?.()}</div>
               </VcUpload>
             </div>
             {renderUploadList()}