Fix sampler.py issues creating sequence-score mismatches

[carlossolugen]

Identified issues and corrected them that led to sequences not matching the scores the sampler returned, as well as sequences being accepted despite accepted being false as a side effect of the bug in how state was kept across the sampling.

[pemami4911]

Sorry for the lengthy time it took to get around to this PR! Not much free time these days..

• Can you remove the environment.yml
• Can you delete any new print statements or unused, commented out code
• There are many changes in sampler.py so it's difficult for me to review this without a detailed comment describing the bugs that you fixed, and how you fixed them. Can you please provide a description here as a comment the details