refactor(接口测试): 优化har导入时覆盖模式的默认值 (#15585)

--bug=1014709 --user=王孝刚
【接口测试】HTTP协议-接口导入-选择HAR格式-导入模式默认为覆盖-其它格式导入模式默认不覆盖
https://www.tapd.cn/55049933/s/1196958

Co-authored-by: wxg0103 <727495428@qq.com>

frontend/src/business/components/api/automation/scenario/common/ScenarioImport.vue

@@ -201,9 +201,6 @@ export default {
           break;
         }
       }
-      if (this.selectedPlatformValue === 'Har') {
-        this.formData.modeId = 'fullCoverage';
-      }
     }
   },
   computed: {

frontend/src/business/components/api/definition/components/import/ApiImport.vue

@@ -300,7 +300,7 @@ export default {
           break;
         }
       }
-      if (this.selectedPlatformValue === 'Har' || this.selectedPlatformValue === 'ESB') {
+      if (this.selectedPlatformValue === 'ESB') {
         this.formData.modeId = 'fullCoverage';
         this.$refs.form.clearValidate();
       }