fix(接口测试): 条件控制器兼容拼接函数

--bug=1015823 --user=赵勇 【接口测试】github#16871，jemter函数${__V拼接变量在条件控制器中不生效 https://www.tapd.cn/55049933/s/1227720

backend/src/main/java/io/metersphere/api/dto/definition/request/controller/MsIfController.java

@@ -103,7 +103,8 @@ public class MsIfController extends MsTestElement {
 
     public String getCondition() {
         String key = getContentValue();
-        String variable = (StringUtils.isEmpty(key) || key.equals(this.variable)) ? "\"" + this.variable + "\"" : "vars.get('" + key + "')";
+        String variable = (StringUtils.isEmpty(key) || key.equals(this.variable)) || key.startsWith("__V") ?
+                StringUtils.join("\"", this.variable, "\"") : StringUtils.join("vars.get('", key, "')");
         String operator = this.operator;
         String value;
         if (StringUtils.equals(operator, "<") || StringUtils.equals(operator, ">")) {