Revert set_jh_default_local_zh

Fix issue: https://gitlab.com/gitlab-jh/gitlab/-/issues/327

Revert MR(Feature: Set JH default language to zh_CN): https://gitlab.com/gitlab-jh/gitlab/-/merge_requests/112

Revert merged commit: https://gitlab.com/gitlab-jh/gitlab/-/commit/b351699c8edae8e19bad43964e127a6609eb1bf5

Revert Reason

We cannot recklessly modify the system language.

https://gitlab.com/gitlab-jh/gitlab/-/issues/327 is a case,

at the time of writing Importer (common_metrics.yml), it only supports English.