feat(misconf): Support private registries for misconf check bundle

[JeffResc]

Description

This proposed change allows the policy bundle repository specified with --policy-bundle-repository to be pulled from a private registry using specified username and password.

Related issues

• Close feat(misconf): Support private registries for misconf check bundle #6266

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

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[nikpivkin]

LGTM

[DmitriyLewen]

LGTM

[knqyf263]

We're planning to cut v0.50.1. We'll merge this PR after that.

[dabo-devconsole]

Really nice! Just what I'm currently facing with. You mentioned --username + --password. Will --registry-token (oauth) also be possible?

[simar7]

Really nice! Just what I'm currently facing with. You mentioned --username + --password. Will --registry-token (oauth) also be possible?

This PR just passes along the currently supported registry options by Trivy which are documented here.