Fix default value in verify-signed-rpms

[lcarva]

The value of the FAIL_UNSIGNED parameter of the verify-signed-rpms Task is used when calling the rpm_verifier binary. An empty string value is not a valid value result in this error:

Usage: rpm_verifier [OPTIONS]
Try 'rpm_verifier --help' for help.

Error: Invalid value for '--fail-unsigned': '' is not a valid boolean.

This commit changes the default value to "false". This is both valid and inline with ADR-14.

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[yftacherzog]

This task is maintained in tekton-tools and replicated here, so changes should be made there, where it's also tested.
We should probably mention that on the README.
https://github.com/redhat-appstudio/tekton-tools/blob/main/tasks/verify-signed-rpms/0.1/verify-signed-rpms.yaml

[lcarva]

This task is maintained in tekton-tools and replicated here, so changes should be made there, where it's also tested. We should probably mention that on the README. https://github.com/redhat-appstudio/tekton-tools/blob/main/tasks/verify-signed-rpms/0.1/verify-signed-rpms.yaml

Thanks for the info! That is a private repo with forking disabled. I cannot contribute.

[yftacherzog]

This task is maintained in tekton-tools and replicated here, so changes should be made there, where it's also tested. We should probably mention that on the README. https://github.com/redhat-appstudio/tekton-tools/blob/main/tasks/verify-signed-rpms/0.1/verify-signed-rpms.yaml

Thanks for the info! That is a private repo with forking disabled. I cannot contribute.

I added you. Let me know if you're now able to create a branch on the repo itself and create a PR.

[lcarva]

Let's follow up in https://github.com/redhat-appstudio/tekton-tools/pull/131