update zh-cn/release-notes/OpenHarmony-v2.2-beta2.md.

Signed-off-by: Nzengyawen <zengyawen1@huawei.com>

zh-cn/release-notes/OpenHarmony-v2.2-beta2.md

@@ -37,7 +37,7 @@
 
 通过repo + ssh 下载（需注册公钥，请参考[码云帮助中心](https://gitee.com/help/articles/4191)）。
 
-```
+```shell
 repo init -u git@gitee.com:openharmony/manifest.git -b refs/tags/OpenHarmony-v2.2-Beta2 --no-repo-verify
 repo sync -c
 repo forall -c 'git lfs pull'
@@ -47,7 +47,7 @@ repo forall -c 'git lfs pull'
 
 通过repo + https 下载。
 
-```
+```shell
 repo init -u https://gitee.com/openharmony/manifest.git -b refs/tags/OpenHarmony-v2.2-Beta2 --no-repo-verify
 repo sync -c
 repo forall -c 'git lfs pull'