du: add zh translation

[witt-bit]

• [✔] The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• [✔] The page(s) have at most 8 examples.
• [✔] The page description(s) have links to documentation or a homepage.
• [✔] The page(s) follow the content guidelines.
• [✔] The page(s) follow the style guide.
• [✔] The PR title conforms to the recommended templates.
• Version of the command being documented (if known):

The du command pages exist in both osx and common. They are used in exactly the same way. I suggest removing them from osx.

[tldr-bot]

Hello! I've noticed something unusual when checking this PR:

• The page pages.zh/common/du.md is outdated, based on the command contents itself, compared to the English page.

Is this intended? If so, just ignore this comment. Otherwise, please double-check the commits.

[witt-bit]

close #15479