fix of the function proportionBySport. Taking into account mli42 remark (#232)

* fix of the function proportionBySport. Taking into account mli42 remark

* refactor: too much hint

Co-authored-by: Quentin FEUILLADE--MONTIXI <58710693+qfeuilla@users.noreply.github.com>

Author: madvid

module04/subject/en.subject.tex

@@ -325,7 +325,7 @@ \section*{Examples}
 from ProportionBySport import proportion_by_sport
 proportion_by_sport(data, 2004, 'Tennis', 'F')
 # Output
-0.01935634328358209
+0.019302325581395347
 \end{minted}
 
 We assume that we are always using appropriate arguments as input,