fix black and isort linting

[fdamken]

reformatting and updating the action

[codecov]

Codecov Report

Merging #99 (98dfea1) into master (edff8c5) will decrease coverage by 3.44%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #99      +/-   ##
==========================================
- Coverage   64.84%   61.40%   -3.44%     
==========================================
  Files         199      199              
  Lines       20120    20120              
==========================================
- Hits        13046    12355     -691     
- Misses       7074     7765     +691     

Flag	Coverage Δ
unittests	61.40% <100.00%> (-3.44%)	⬇️

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

Files	Coverage Δ
...yrado/pyrado/algorithms/episodic/predefined_lqr.py	0.00% <ø> (ø)
Pyrado/pyrado/algorithms/meta/adr.py	34.00% <ø> (ø)
...ado/algorithms/regression/timeseries_prediction.py	89.14% <ø> (ø)
Pyrado/pyrado/algorithms/step_based/dql.py	50.51% <ø> (ø)
Pyrado/pyrado/algorithms/step_based/gae.py	85.12% <ø> (ø)
Pyrado/pyrado/algorithms/step_based/ppo.py	93.10% <ø> (ø)
...rado/pyrado/environments/rcspysim/planar_insert.py	0.00% <ø> (-91.94%)	⬇️
Pyrado/pyrado/policies/feed_forward/poly_time.py	83.44% <100.00%> (ø)
Pyrado/pyrado/sampling/parallel_rollout_sampler.py	78.78% <ø> (ø)
Pyrado/pyrado/sampling/sequences.py	85.41% <ø> (ø)

... and 24 files with indirect coverage changes