fix: 资源池镜像长度进行限制

--bug=1027746 --user=刘瑞斌 【系统设置】github#25536，【系统设置】-系统-测试资源池：创建资源池-镜像。输入字符数过长时点击确定提示异常信息“SQL error happened, please check logs.” https://www.tapd.cn/55049933/s/1392386

system-setting/frontend/src/business/system/pool/TestResourcePool.vue

@@ -324,6 +324,9 @@ export default {
             trigger: 'blur'
           }
         ],
+        image: [
+          {max: 100, message: this.$t('commons.input_limit', [0, 100])}
+        ],
         description: [
           {max: 60, message: this.$t('commons.input_limit', [0, 60]), trigger: 'blur'}
         ],