test(ws): enhance e2e test setup and cleanup

[Adembc]

This PR introduces the following changes:

• Removes the prompt for end-to-end (E2E) test execution.
• Adds checks to verify if the CertManager and Prometheus operators are already installed. This prevents reinstallation and avoids unnecessary deletion.
• Added support for skipping CertManager installation with the environment variable CERT_MANAGER_INSTALL_SKIP.
• Added support for skipping Prometheus installation with the environment variable PROMETHEUS_INSTALL_SKIP.
• Enhances the E2E test setup and cleanup.

These changes follow discussions with the Kubebuilder maintainer, who has already merged similar updates into Kubebuilder in this PR.

Note:

• PROMETHEUS_INSTALL_SKIP is currently set to true by default because the Prometheus operator is not required at this time. However, it might be needed in the future, so the option remains configurable.

[google-oss-prow[bot]]

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