docs: Add note about libvirt-sock error

[alvarolinarescabre]

Pull Request

What? (description)

Add error with libvirt-sock

Why? (reasoning)

I found the error if not installed libvirt

Acceptance

Please use the following checklist:

• you linked an issue (if applicable)
• you included tests (if applicable)
• you ran conformance (make conformance)
• you formatted your code (make fmt)
• you linted your code (make lint)
• you generated documentation (make docs)
• you ran unit-tests (make unit-tests)

See make help for a description of the available targets.

Add note about libvirt-sock error on vagrant + libvirt guide

[frezbo]

I think this is mixing up two PR's

[github-actions]

This PR is stale because it has been open 45 days with no activity.