fix: detail matplotlib version number

Author: siemdejong

settings.ini

@@ -37,7 +37,7 @@ language = English
 status = 3
 user = acclab
 
-requirements = fastcore pandas~=1.5.0 numpy~=1.23.5 matplotlib~=3.8 seaborn~=0.12.2 scipy~=1.9.3 datetime statsmodels lqrt
+requirements = fastcore pandas~=1.5.0 numpy~=1.23.5 matplotlib~=3.8.4 seaborn~=0.12.2 scipy~=1.9.3 datetime statsmodels lqrt
 dev_requirements = pytest~=7.2.1 pytest-mpl~=0.16.1
 
 ### Optional ###