Add OPA examples on pathType restrictions

[rikatz]

What this PR does / why we need it:

With the upcoming restriction on pathType and usages, it is good to have an example on restrictions using OPA

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[longwuyuan]

Do you need to add a example for "should allow" for pathType "Prefix". Or one example for "should allow" is enough. I don't know so asking.

[rikatz]

I don't think so, the idea here is just to teach people how they can use OPA to block a specific pathType. We have a lot of cases, like blocking characters, allowing pathType if an annotation exists, etc and I don't want to cover all of them, just let them know they can use OPA to protect the requests

[longwuyuan]

Now I need to check if Kyverno use OPA at all. Someone may ask.

[rikatz]

We dont need to cover all cases, this is an example. We need people to be aware they need to apply policies :)

[longwuyuan]

We dont need to cover all cases, this is an example. We need people to be aware they need to apply policies :)

ok :-)

[tao12345666333]

/lgtm
/hold

But I think we should add some text description, like the description in this PR.

Users can have a clearer understanding of the applicable scenarios of this example

[tao12345666333]

/lgtm
/hold cancel

[tao12345666333]

Suggested change

	This means that the Ingress Admins (the persona who deployed the Ingress Controller) should trust the users
	This means that the Ingress Admins (the person who deployed the Ingress Controller) should trust the users

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: rikatz, tao12345666333

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