[Stream:Config] Add allowMsgSchedules configuration

[zlatkoverk]

New config introduced in NATS 2.12

https://nats-io.github.io/nats.net/api/NATS.Client.JetStream.Models.StreamConfig.AllowMsgSchedules.html#NATS_Client_JetStream_Models_StreamConfig_AllowMsgSchedules

[nekufa]

hi @zlatkoverk, thanks for the contribution. return type should be nullable too

TypeError: Basis\Nats\Stream\Configuration::getAllowMsgSchedules(): Return value must be of type bool, null returned

[zlatkoverk]

hi @zlatkoverk, thanks for the contribution. return type should be nullable too

TypeError: Basis\Nats\Stream\Configuration::getAllowMsgSchedules(): Return value must be of type bool, null returned

@nekufa Fixed! Thanks