mockery: don't use boilerplate

Author: wikkyk

.mockery.yaml

@@ -2,7 +2,6 @@ quiet: false
 disable-version-string: true
 with-expecter: true
 include-auto-generated: false
-boilerplate-file: hack/boilerplate.go.txt
 packages:
   github.com/ionos-cloud/cluster-api-provider-proxmox/pkg/proxmox:
     interfaces: