docs: add guide for using BackendRef Filters

[Xunzhuo]

Description:

Describe the desired behavior, what scenario it enables and how it
would be used.

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Any extra documentation required to understand the issue.

[Manoramsharma]

Hi @Xunzhuo, can you please provide some more context about the issue as I would like to take this up.

[Xunzhuo]

Here is the related pull request: #3246

[Manoramsharma]

I will open a PR soon to it, can you please assign it to me.

[Manoramsharma]

HI @shawnh2 @Xunzhuo I have gone through the implementation of BackendRef filters in the k8s gateway-api with the EG, As per my understanding I think we have to update under API section of the documentation but I am bit confused, can you please guide me where to make the changes exactly?

[Manoramsharma]

@zirain Can you please help me with this one? I am bit confused, can you please guide me where to make the changes exactly?

[zirain]

#3246 give an example about how to add some question before send to backend.

[github-actions]

This issue has been automatically marked as stale because it has not had activity in the last 30 days.