fix(测试跟踪): 修复测试计划关联接口页面切换项目，高级搜索未重置的缺陷

--bug=1025858 --user=王孝刚 【测试跟踪】测试计划-关联接口用例-高级搜索后切换项目-搜索条件未重置
https://www.tapd.cn/55049933/s/1367409

test-track/frontend/src/business/plan/view/comonents/api/RelevanceApiList.vue

@@ -186,6 +186,7 @@ export default {
       if (this.$refs.msEnvironmentSelect) {
         this.$refs.msEnvironmentSelect.environmentId = "";
       }
+      this.condition.combine = undefined;
       this.clear();
     }
   },

test-track/frontend/src/business/plan/view/comonents/api/RelevanceCaseList.vue

@@ -274,6 +274,7 @@ export default {
       if (this.$refs.msEnvironmentSelect) {
         this.$refs.msEnvironmentSelect.environmentId = "";
       }
+      this.condition.combine = undefined;
       this.clear();
     },
     getTagToolTips(tags) {