[Feature]Add support for sequence parallel

[cascade812]

add support for sequence parallel.
TODO support combination with PP
TODO support more models

[github-actions]

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @cascade812.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[mergify]

⚠️ The sha of the head commit of this PR conflicts with #14908. Mergify cannot evaluate rules on this PR. ⚠️