fix defaults for keyring config

[skurnevich]

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[github-actions]

build 5668 SUCCEEDED.
Link to workflow run: https://github.com/zowe/zowe-install-packaging/actions/runs/9974537776

[github-actions]

Test workflow 5048 is started.
Running install test: Convenience Pax
The zowe artifact being used by this test workflow: libs-snapshot-local/org/zowe/2.17.0-PR-3917/zowe-2.17.0-pr-3917-5668-20240717125733.pax
Running on machine: zzow07
Result: SUCCESS
Link to workflow run: https://github.com/zowe/zowe-install-packaging/actions/runs/9974664740

[1000TurquoisePogs]

This is an acceptable compromise to me.

What this would do in effect ensure dname and validity sections whenever keyrings are used.
This is more broad than necessary, but will prevent other bugs for now until a more specific solution is made.
The consequence is you'll end up with dname and validity environment variables set in scenarios where they're actually unused.
I do not expect any components/extensions would be reading "zowe.setup.certificate.keyring.dname" for any reason, so I think this is a fine solution for now.