fix: update k8s values file to include secmon image for NIM K8s deployment

[balakoteswar]

Proposed changes

Fixed the image paths and added a new secmon image to values.yaml file for NIM k8s helm deployment as part of NIM v2.19.0 release.

Testing: Tested locally.

Closes # N/A

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[cjain-f5]

LGTM