changed buffer add function call

[kim-mskw]

changed buffer add function call to not only add the first value of the observations 50 times.

I am wondering how it learned anything with these observations in the buffer...

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (3bddb13) 78.44% compared to head (e18d165) 78.44%.

Additional details and impacted files

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[nick-harder]

oh wow, that is weird error. I believe at some point observation contained past and future observations, so this was required. But at some point we probably shifted to use only one observation since next one could be sampled easily, but this part stayed