GHSA-rf84-wr5g-m3rp: CAPM3 vulnerable to Cross-Namespace resource access

CAPM3 is Metal3’s Cluster API (CAPI) provider for baremetal provisioning in Kubernetes. Multiple cross-namespace access control vulnerabilities in Cluster API Provider Metal3 allow users with permissions to create or modify CAPM3 resources in one namespace to reference, read, or claim resources belonging to other namespaces.