Review docstrings checkmarcked as best practice

[OriolAbril]

Minor fixes to docstrings marked as best practices already so they can serve as example in the coming open source working sessions.

[codecov]

Codecov Report

Merging #5919 (f6e387f) into main (3bf95ce) will increase coverage by 0.03%.
The diff coverage is 97.59%.

@@            Coverage Diff             @@
##             main    #5919      +/-   ##
==========================================
+ Coverage   89.50%   89.53%   +0.03%     
==========================================
  Files          73       73              
  Lines       13267    13267              
==========================================
+ Hits        11874    11878       +4     
+ Misses       1393     1389       -4     

Impacted Files	Coverage Δ
pymc/distributions/__init__.py	100.00% <ø> (ø)
pymc/distributions/continuous.py	97.98% <ø> (ø)
pymc/distributions/timeseries.py	78.64% <ø> (ø)
pymc/sampling.py	82.41% <ø> (ø)
pymc/smc/sample_smc.py	83.22% <ø> (ø)
pymc/smc/smc.py	96.45% <ø> (ø)
pymc/variational/approximations.py	87.32% <ø> (+0.62%)	⬆️
pymc/variational/opvi.py	87.04% <ø> (+0.02%)	⬆️
pymc/distributions/discrete.py	99.21% <85.71%> (-0.52%)	⬇️
pymc/__init__.py	100.00% <100.00%> (ø)
... and 14 more

[OriolAbril]

Should be ready to merge now. If something else still needed fixing please take over to get it merged before the open source working sessions

[michaelosthege]

Nice one!