It's not possible to share BMC secrets between BareMetalHosts

Before the {product-title} {product-version} release, a `BareMetalHost` object would exclusively own a Baseboard Management Console (BMC) Secret, `BMCSecret`, custom resource (CR) with defined user credentials. A `BareMetalHost` object could not share its `BMCSecret` CR with another `BareMetalHost` object, even if the other object contained identical user credentials. A `baremetal-operator` would need to create a new `BMCSecret` CR for the other `BareMetalHost` object. The {product-title} {product-version} removes exclusive ownership of a `BMCSecret` CR for a `BareMetalHost` object, so that a `BMCSecret` CR can be shared among `BareMetalHost` objects. (link: https://issues.redhat.com/browse/OCPBUGS-1080 [* OCPBUGS-1080 *])