Update zh_cn.po

[TC999]

修复一些翻译错误

fix some trans error

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[github-actions]

Errors and warnings found by git-po-helper in workflow #825:

INFO no missing blobs of po/* in partial clone    
------------------------------------------------------------------------------
ERROR commit 04c692d: found changes beyond "po/" directory: 
ERROR 		git-gui/po/zh_cn.po                        
ERROR                                              
ERROR commit 04c692d: break because this commit is not for git-l10n 
INFO checking commits: 0 passed, 1 failed.        
------------------------------------------------------------------------------
INFO downloading pot file from https://github.com/git-l10n/pot-changes/raw/pot/master/po/git.pot 

ERROR: fail to execute "git-po-helper check-commits"