builder.yml: Reinstall vagrant(-libvirt) if needed

builder.yml: Reinstall vagrant(-libvirt) if needed

Avoids:

```
Vagrant failed to properly resolve required dependencies. These
errors can commonly be caused by misconfigured plugin installations
or transient network issues. The reported error is:
nokogiri requires Ruby version >= 3.2, < 4.1.dev. The current ruby version is 2.7.4.191.
```

Which happens when an old vagrant version is installed on a builder then the version of vagrant provided in the chacra repo is newer.

Signed-off-by: David Galloway <david.galloway@ibm.com>