Add ext-authz route example

[bochengchu]

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• ✅ login: bochengchu / name: Bo-Cheng Chu (a00c6e2)

[istio-testing]

Hi @bochengchu. Thanks for your PR.

I'm waiting for a istio member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[ericvn]

/ok-to-test

[istio-testing]

@bochengchu: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
gencheck_istio.io	a00c6e2	link	true	/test gencheck
lint_istio.io	a00c6e2	link	true	/test lint

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.

[craigbox]

Please run make gen and included the generated files in your PR.

[craigbox]

Suggested change

	## Route with external authorization
	## Route with external authorization

[craigbox]

(required to fix lint error.)