Refactor code

[dungscout96]

These task parameters such as

eeg-ssl/libs/ssl_utils.py

Line 203 in 8d4825e

win_length = 50,

should be put in the task_params dictionary, replacing the current "mask_probability" key as it was for the MaskedContrastiveLearning task. This should be done for all tasks in Banville paper

[makhalid1999]

I have refactored the code, and added a standard implementation for all, and taking guidance from the update on the main branch, I have implemented the Trainer class, which would run for all tasks. My implementation is on the banville branch:

https://github.com/sccn/eeg-ssl/blob/banville/libs/ssl_utils.py