use the allowed upgrades list when validating version upgrades Beginning with v24.2, some releases are innovation releases which can be skipped during upgrading. The ListClusterMajorVersions API returns information on allowed upgrade paths, which we now use to validate whether an upgrade is possible in `apply`. Additional validation (cluster state, etc) is performed server-side within the API, so this validation is mostly to catch the most common type of error with a faster, more helpful error message, and not to be exhaustive.