docs: add an Async redis Watcher

[kevinkelin]

docs: add an Async redis Watcher

[casbin-bot]

@tangyang9464 @JalinWang @imp2002 please review

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[CLAassistant]

All committers have signed the CLA.

[Selflocking]

Thanks for submitting the PR. In order to pass the Semantic PR check, please change your PR and commit msg to: docs: add an Async redis Watcher

[kevinkelin]

Thanks for submitting the PR. In order to pass the Semantic PR check, please change your PR and commit msg to: docs: add an Async redis Watcher

OK, I change the PR title and commit to docs: add an Async redis Watcher, but how to trigger the checker?

[Selflocking]

Thanks for submitting the PR. In order to pass the Semantic PR check, please change your PR and commit msg to: docs: add an Async redis Watcher

OK, I change the PR title and commit to docs: add an Async redis Watcher, but how to trigger the checker?

[hsluoyz]

@kevinkelin plz fix CI error:

[kevinkelin]

Details

I did't change that file, I think this code have no problem, or how to fix that? @hsluoyz

[hsluoyz]

@Selflocking how to resolve this?