Add 10-pg_clean.en.md

[Amber-niubi]

https://github.com/OpenTenBase/docs/blob/main/docs/guide/10-pg_clean.md has been translated into English.

[bartdong]

Thank you for your contribution.
Please check the comments and optimize. Thank you!

[bartdong]

Please check and optimize all the English version again in case I missed any problems. Thank you!

[bartdong]

Line 153 needs to be optimized.
Line 244 is wrong.
Line 394 is wrong.
Line 569 'Materialize materialization' repeat.
Line 628 join spell (happens also in Chinese version)
Please check and optimize all the English version again in case I missed any problems. Thank you!

[CLAassistant]

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