[Docs] Document how to use Express middleware for authorization

[dhmlau]

Description

Document how to use Express middleware for authorization.

Related to: #1293

[stale]

This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[dhmlau]

@deepakrkris @emonddr @jannyHou, could you please review if that's something we can do today and/or we have documentation already covered? Thanks.

[jannyHou]

After #5118 landed it should be easier for us to add express middleware.

@deepakrkris has a PoC PR showing use Express middleware for authentication in #5302. We can find some outstanding middleware for authorization and try the similar approach.

[stale]

This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[stale]

This issue has been closed due to continued inactivity. Thank you for your understanding. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository.