[Docs] Add faq in dev-1.x branch

[Renzhihan]

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Motivation

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Modification

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[MeowZheng]

The faq is in docs/en/notes/faq.md for mmseg 1.x, and I think it is not necessary to add the version dependency of mmseg 0.x

[Renzhihan]

The faq is in docs/en/notes/faq.md for mmseg 1.x, and I think it is not necessary to add the version dependency of mmseg 0.x

Thanks for your reply, I made a mistake in understanding the task. I will update the docs/en/notes/faq.md later.

[MeowZheng]

please follow #2768 to add the version dependency of 1.x

[Renzhihan]

I follow #2769 to delete the "Why is the log file not created" and other version errors.