zh-CN: Update po/zh-CN.po

[illustager]

Fix merge conflict. Apply the review comments.

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[mgeisler]

Hi @illustager, thanks for fixing the merge conflicts!

I noticed that this PR changes some of the timing information tables:

 #: src/running-the-course/course-structure.md
 msgid "[Tuples and Arrays](../tuples-and-arrays.md) (1 hour)"
-msgstr "[元组和数组](../tuples-and-arrays.md)（1 小时）"
+msgstr "[元组和数组](../tuples-and-arrays.md) (1 hour)"
 
 #: src/running-the-course/course-structure.md
 msgid "[References](../references.md) (50 minutes)"
-msgstr "[引用](../references.md)（50 分钟）"
+msgstr "[引用](../references.md) (50 minutes)"
 
 #: src/running-the-course/course-structure.md
 msgid "[User-Defined Types](../user-defined-types.md) (50 minutes)"
-msgstr "[用户定义的类型](../user-defined-types.md)（50 分钟）"
+msgstr "[用户定义的类型](../user-defined-types.md) (50 minutes)"

It seems you're changing the translation of "minutes" back to English, but I'm not sure this is on purpose?

[mgeisler]

It's a bit unfortunate that those tables end up in the translation file at all, I filled #1982 to see if we can improve this.

[mobyw]

It looks like some of the translation is rolled back in this PR.
You can select the lines that need to be changed, find the corresponding location in the latest branch and paste it in and make the changes.