set Async
Sets whether the tick function should be called asynchronously.
This is assumed to be constant for all instances of a block. Should you have a use case where you need to have different blocks be async, please make an issue on the GitHub repository and explain your use case.
WARNING: Settings a block to tick asynchronously could have unintended consequences.
Only set this option if you understand what 'asynchronous' means, and note that you cannot interact with the world asynchronously.