Fix installPackages regex for OS update policy and use its new fields

[jkossak]

Description

This PR propagates:

• the regex fix to the openapi spec: https://github.com/open-edge-platform/infra-core/pull/527/files,
• and change of OSUpdatePolicy fields name (update_packages and update_kernel_command) Apiv2 - rename OSUpdatePolicy fields infra-core#542

Fixes # (issue)

Any Newly Introduced Dependencies

Please describe any newly introduced 3rd party dependencies in this change. List their name, license information and how they are used in the project.

How Has This Been Tested?

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Checklist:

• I agree to use the APACHE-2.0 license for my code changes
• I have not introduced any 3rd party dependency changes
• I have performed a self-review of my code