[kwctl] `kwctl scaffold artifacthub-pkg.yml` doesn't support monorepos

[viccuad]

Currently, doing kwctl scaffold artifacthub-pkg.yml generates an incorrect annotation for the "policy" binary link that gets used in artifacthub.io under "policy" here:

For example, for:
https://artifacthub.io/packages/kubewarden/kubewarden-policy-library/disallow-service-loadbalancer
It incorrectly points to:
https://github.com/kubewarden/policies/releases/download/v1.0.10/policy.wasm

Acceptance criteria

• Generate io.kubewarden.policy.url including the name of the policy to the version tag.
• Remove automation workaround added in fix(ci): fix policy wasm binary link. policies#310.

This is a port of kubewarden/policies#310.