botorch DeprecationError: `fantasize` no longer accepts a boolean for `observation_noise`.

[BeBraveBeCurious]

Hello,

Thank you for sharing the MLMCBO code.

I installed the required packages with the specified versions in the README, including BoTorch == 0.9.2. However, I encountered an issue related to the deprecation of the observation_noise parameter in the fantasize function:

botorch.exceptions.errors.DeprecationError: `fantasize` no longer accepts a boolean for `observation_noise`. 

There are two possible values for observation_noise: True or False. If it was previously set to False, it can be changed to None, as shown by setting observation_noise=None at line 94.

Could you please advise on how to update the observation_noise=True at Line611, Line641, Line644?

Thank you very much.