fix(接口测试): 修复接口定义执行时string取枚举值的缺陷

--bug=1020660 --user=王孝刚 【接口测试】json-schema请求体，string类型的参数值为空时会取枚举值
https://www.tapd.cn/55049933/s/1313197

api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaRunTest.java

@@ -3,10 +3,8 @@ package io.metersphere.api.exec.generator;
 
 import com.google.gson.*;
 import io.metersphere.commons.constants.PropertyConstant;
-import io.metersphere.commons.utils.EnumPropertyUtil;
 import io.metersphere.commons.utils.JSONUtil;
 import io.metersphere.jmeter.utils.ScriptEngineUtils;
-import org.apache.commons.collections4.CollectionUtils;
 import org.apache.commons.collections4.MapUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.json.JSONArray;
@@ -14,7 +12,6 @@ import org.json.JSONObject;
 import org.springframework.util.NumberUtils;
 
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 
@@ -252,12 +249,6 @@ public class JSONSchemaRunTest {
             if (isMock(object)) {
                 String value = ScriptEngineUtils.buildFunctionCallString(object.get(PropertyConstant.MOCK).getAsJsonObject().get(PropertyConstant.MOCK).getAsString());
                 return value;
-            } else if (object.has(PropertyConstant.ENUM)) {
-                List<Object> list = EnumPropertyUtil.analyzeEnumProperty(object);
-                if (CollectionUtils.isNotEmpty(list)) {
-                    int index = (int) (Math.random() * list.size());
-                    return list.get(index);
-                }
             }
         } catch (Exception e) {
             return object.get(PropertyConstant.MOCK).getAsJsonObject().get(PropertyConstant.MOCK);