Vagrant: Test test_vagrant_root[box_url] fails due to missing box

[dinadins]

The test's molecule.yml references a remote Vagrant box that has been removed - CentOS-Stream-Vagrant-9-20230704.1.x86_64.vagrant-libvirt.box. Consequently the test fails with error:

There was an error while downloading the metadata for this box.
The error message is shown below:

The requested URL returned error: 404

The box URL is indeed dead, its entry is missing from the image page; there are no libvirt boxes older than a year. Perhaps referencing a "historical" image like CentOS-8-Vagrant-8.4.2105-20210603.0.x86_64.vagrant-libvirt.box will be more future-proof - however, these do not have a checksum (part of the testcase) which will need to be calculated manually. For this one sha256sum returns "37cc017738bf12cafce3a97c4de73526452da6332cc5c0516723988644e62620".

With these values in test/vagrant-plugin/scenarios/molecule/box_url/molecule.yml the test passes.