fix(系统设置): 插件管理中上传jar包再次上传时带了之前上传的jar包

--bug=1008289 --user=王孝刚 【系统设置】插件管理，上传jar包再次上传，带了之前上传的jar包
https://www.tapd.cn/55049933/s/1074477

frontend/src/business/components/settings/plugin/JarConfig.vue

@@ -117,6 +117,7 @@ export default {
               this.fileList = [];
             });
           } else {
+            this.fileList = [];
             return false;
           }
         }

frontend/src/business/components/settings/plugin/PluginConfig.vue

@@ -57,7 +57,7 @@
 
       </el-table>
     </el-card>
-    <el-dialog :title="$t('commons.import')" :visible.sync="dialogVisible" @close="close">
+    <el-dialog :title="$t('commons.import')" :visible.sync="dialogVisible" @close="close" destroy-on-close>
       <ms-jar-config @close="close"/>
     </el-dialog>
     <ms-script-view ref="scriptView"/>