Move to a new neo-go API

[fyrchik]

Old neo-go RPC client API is deprecated. Move to the Actor API, I believe morph client can be considerably simplified.
Let's do it 1 by 1 in small PRs, if possible.

pkg/morph/client/multi.go:82:12                                         staticcheck  SA1019: c.client.Notifications is deprecated: please, use custom channels with ReceiveBlocks, ReceiveTransactions, ReceiveExecutionNotifications, ReceiveExecutions, ReceiveNotaryRequests methods to subscribe for notifications. This field will be removed in future versions.
pkg/morph/client/notary.go:426:15                                       staticcheck  SA1019: c.client.SignAndPushP2PNotaryRequest is deprecated: please use Actor from the notary subpackage. This method will be deleted in future versions.
pkg/morph/client/notary.go:520:20                                       staticcheck  SA1019: c.client.CalculateNotaryFee is deprecated: NeoGo calculatenetworkfee method handles notary fees as well since 0.99.3, so this method is just no longer needed and will be removed in future versions.
pkg/morph/client/notary.go:539:15                                       staticcheck  SA1019: c.client.SignAndPushP2PNotaryRequest is deprecated: please use Actor from the notary subpackage. This method will be deleted in future versions.
pkg/morph/client/notifications.go:39:13                                 staticcheck  SA1019: c.client.SubscribeForExecutionNotifications is deprecated: please, use ReceiveExecutionNotifications. This method will be removed in future versions.
pkg/morph/client/notifications.go:67:12                                 staticcheck  SA1019: c.client.SubscribeForNewBlocks is deprecated: please, use ReceiveBlocks. This method will be removed in future versions.
pkg/morph/client/notifications.go:102:13                                staticcheck  SA1019: c.client.SubscribeForNotaryRequests is deprecated: please, use ReceiveNotaryRequests. This method will be removed in future versions.
pkg/morph/client/notifications.go:216:12                                staticcheck  SA1019: cli.SubscribeForNewBlocks is deprecated: please, use ReceiveBlocks. This method will be removed in future versions.
pkg/morph/client/notifications.go:229:13                                staticcheck  SA1019: cli.SubscribeForExecutionNotifications is deprecated: please, use ReceiveExecutionNotifications. This method will be removed in future versions.
pkg/morph/client/notifications.go:245:14                                staticcheck  SA1019: cli.SubscribeForNotaryRequests is deprecated: please, use ReceiveNotaryRequests. This method will be removed in future versions.

[fyrchik]

neofs-adm can wait until neo-go starts to provide a local client itself.