Version 3.3

• Add issuer_country and subject_country to Certificate class

• Use re_path for urls

• Replace all ugettext_lazy calls with gettext_lazy

• Use force_str instead of the force_text which was removed in django 4.0

• Update test matrix:

  • Remove python 3.6 and 3.7
  • Use latest poetry in CI
  • Add python 3.9 and 3.11
  • Add django 4.0 and 4.1
  • Remove django 2.0