Type Alias migrate_pool_to_delegate_stake

Migrate pool from [adapter::StakeStrategyType::Transfer] to [adapter::StakeStrategyType::Delegate].

Fails unless [crate::pallet::Config::StakeAdapter] is of strategy type: [adapter::StakeStrategyType::Delegate].

This call can be dispatched permissionlessly, and refunds any fee if successful.

If the pool has already migrated to delegation based staking, this call will fail.