As a developer, I want to be able to write router e2e tests without needing to push code to a different repository

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As part of improving the router tests suite, without needing to write tests on different repos (like origin), we can rely on the `openshift-tests-extension` enhancement to write router e2e test on its own repo, but guarantee it will be executed as part of Origin tests.

Some references: 

• https://github.com/openshift/enhancements/blob/master/enhancements/testing/openshift-tests-extension.md
• https://github.com/openshift-eng/openshift-tests-extension/tree/main
• https://github.com/openshift/openshift-apiserver/blob/main/cmd/openshift-apiserver-tests-ext/main.go (openshift-apiserver uses this feature)
• https://github.com/openshift/origin/pull/30042
• https://github.com/openshift/cluster-storage-operator/pull/593
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