fix(接口测试): 新建用例未使用公用环境

--bug=1009054 --user=lyh
【github#8623】接口用例测试时，如果这个用例没选择过环境，右上角上面选择了没用
https://www.tapd.cn/55049933/s/1084231

Closes #8623

frontend/src/business/components/api/definition/components/case/ApiCaseList.vue

@@ -267,7 +267,8 @@ export default {
     },
     getTestCase() {
       return new Promise((resolve) => {
-        this.environment = "";
+        let commonUseEnvironment = this.$store.state.useEnvironment;
+        this.environment = commonUseEnvironment ? commonUseEnvironment : "";
         this.result = this.$get("/api/testcase/findById/" + this.testCaseId, response => {
           let apiCase = response.data;
           if (apiCase) {