Fix: compatibility Django4.0; change url import from django.urls
merge PR of Krzysztof Hoffmann krzysiekpl@gmail.com
handle warnnings; added docker test setup; update packages;
Fix: compatibility Django4.0; change url import from django.urls
merge PR of Krzysztof Hoffmann krzysiekpl@gmail.com
handle warnnings; added docker test setup; update packages;