!11248 fix doc issue

Merge pull request !11248 from laoyitong/1104

zh-cn/application-dev/reference/apis/js-apis-testRunner.md

@@ -29,7 +29,7 @@ export default class UserTestRunner implements TestRunner {
     onPrepare() {
         console.log("Trigger onPrepare")
     }
-    onRun(){}
+    onRun() {}
 };
 ```
 
@@ -47,9 +47,9 @@ onRun(): void
 
 ```js
 export default class UserTestRunner implements TestRunner {
-    onPrepare() {
+    onPrepare() {}
+    onRun() {
         console.log("Trigger onRun")
     }
-    onRun(){}
 };
 ```