修复relative container用例编译问题

Signed-off-by: Nxiexiyun <xiexiyun@huawei.com>

zh-cn/application-dev/reference/arkui-ts/ts-container-relativecontainer.md

@@ -37,10 +37,6 @@ RelativeContainer()
 @Entry
 @Component
 struct Index {
-  build() {
-    @Entry
-    @Component
-    struct Index {
   build() {
     Row() {
 
@@ -96,8 +92,7 @@ struct Index {
     }
     .height('100%')
   }
-    }
-  }
 }
+
 ```
 ![relative container](figures/relativecontainer.png)
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