Remove problematic placeholder vars

[gotmax23]

Remove problematic placeholder vars

[mwperina]

Hi @gotmax23 ,

placeholders in the collection were introduced due to inability to provide the same namespace used for upstream collection within Automation Hub as a fully supported collection by RH.
Before Automation Hub introduction oVirt Ansible modules were included within ansible 2.y distribution and oVirt Ansible roles were available in Galaxy and specific version were test and included in Red Hat Virtualization packaged as RPM, which mean that RHV customers could use any playbook tested on upstream and without any changes they could used it for RHV. Unfortunately when Automation Hub was introduced we needed to put oVirt Ansible Collection under redhat.rhv namespace, which completely broke our compatibility between upstream and downstream. So we were able to solve that within RHV RPMs, where we provide both namespaces.

And we definitely don't want to have 2 repositories, one for ovirt.ovirt and one for redhat.rhv, because that mean much more work and our resources are very limited.

Also we are running sanity tests as a part of our GH CI:
https://github.com/oVirt/ovirt-ansible-collection/blob/master/.github/workflows/build.yaml#L11

[mwperina]

This was also discussed in #256 but without a resolution