OSDOCS-19022: Adding RHEL subscriptions info to ROSA/OSD Virtualization

[otikhomi]

Version(s):
4.21+

Issue:
https://redhat.atlassian.net/browse/OSDOCS-19022

Link to docs preview:
The assembly about-virt.adoc is reused in 4 docs sets:

• OSD
• ROSA
• ROSA Classic
• OCP doc remains untouched and looks the same as the published content

QE review:
N/A

Additional information:
This PR:

• Adds new content as requested. Since content is conceptual, it's placed higher in a module, before the "how to" part.
• Removes (conditionalizes) a duplicate paragraph about OVN-Kubernetes and related link (Certified OpenShift CNI Plug-ins) from ROSA/OSD docs.
• Hides (conditionalizes) an admonition and moves the content to the ROSA/OSD-only paragraph. Also adds back a link "OVN-Kubernetes purpose" mentioned in that admonition.

[openshift-ci-robot]

@otikhomi: This pull request references OSDOCS-19022 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the story to target the "5.0.0" version, but no target version was set.

Details

In response to this:

Version(s):
4.21+

Issue:
https://redhat.atlassian.net/browse/OSDOCS-19022

Link to docs preview:

QE review:
N/A

Additional information:
Also removing duplicate info about OVN-Kubernetes and commenting out some links.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[ocpdocs-previewbot]

🤖 Tue May 26 20:08:40 - Prow CI generated the docs preview:

https://112286--ocpdocs-pr.netlify.app/openshift-dedicated/latest/virt/about_virt/about-virt.html
https://112286--ocpdocs-pr.netlify.app/openshift-enterprise/latest/virt/about_virt/about-virt.html
https://112286--ocpdocs-pr.netlify.app/openshift-rosa-hcp/latest/virt/about_virt/about-virt.html
https://112286--ocpdocs-pr.netlify.app/openshift-rosa/latest/virt/about_virt/about-virt.html

[openshift-ci]

@otikhomi: all tests passed!

Full PR test history. Your PR dashboard.

Details

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