Add instructions for copying container images to private registry
This update adds a new section in the README.md that provides
instructions for copying container images to a private registry
using Skopeo. It includes a command to log in to the Red Hat
registry and an example command for copying the AMQ Broker image
from the Red Hat registry to a specified private registry.
These changes were necessary to assist users who need to transfer
images securely and efficiently to a private environment for
usage. No breaking changes were introduced.
```
