Fix type annotation in class 'ConditionedPotential'.

[schroedk]

Fix type annotation in class 'ConditionedPotential'. Correct return type

of the function 'posterior_estimator_based_potential'

What does this implement/fix? Explain your changes

• The argument potential_fn of the class ConditionedPotential must be of type BasePotential

Does this close any currently open issues?

Fixes #1055

Any relevant code examples, logs, error output, etc?

...

Any other comments?

...

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.90%. Comparing base (8ee2a2c) to head (33679f3).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1222      +/-   ##
==========================================
- Coverage   84.86%   76.90%   -7.96%     
==========================================
  Files          97      101       +4     
  Lines        7677     7941     +264     
==========================================
- Hits         6515     6107     -408     
- Misses       1162     1834     +672     

Flag	Coverage Δ
unittests	76.90% <100.00%> (-7.96%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
sbi/analysis/conditional_density.py	82.53% <100.00%> (-7.79%)	⬇️
.../inference/potentials/posterior_based_potential.py	95.34% <100.00%> (+0.11%)	⬆️
sbi/utils/conditional_density_utils.py	70.13% <100.00%> (-20.78%)	⬇️

... and 32 files with indirect coverage changes

[janfb]

Thanks for fixing this 👍

It makes absolute sense to type as BasePotentials here because we are calling .device and .set_x below.