ManagedClusterSet is introducing new behavior that requires a migration plan to deprecate old API functionality.

https://github.com/open-cluster-management-io/OCM/issues/67#issuecomment-1228018912 

ACM 2.7 / MCE 2.2

[ ] Add exclusiveClustersetLabel selector type in clusterset api v1beta1
[ ] Add clusterset api v1beta2 to remove the support of legacyClustersetLabel selector type
[ ] Add conversion webhook to transform clusterset CRs between v1beta1 and v1beta2
[ ] Change internal consumers(ui/foundation/submarinar-addon/placement) to use clusterset api v1beta2
[ ] Other clusterset consumers (external consumers) can upgrade to clusterset api v1beta2

ACM 2.8 / MCE 2.3

[ ] Mark clusterset api v1beta1 as deprecated
[ ] Migrate storage version of clusterset api to v1beta2
[ ] Other clusterset consumers (external consumers) must upgrade to clusterset api v1beta2

ACM 2.9 / MCE 2.4

[ ] Remove clusterset api v1beta1