Feature: Added initial django-cms 4.0.x compatibility

[Aiky30]

Description

Describe:

• django-cms 4.0.x and backwards compatible changes

Checklist

• I have read the contribution guide
• Code lint checked via inv lint
• changes file included (see docs)
• Usage documentation added in case of new features
• Tests added

[coveralls]

Coverage decreased (-0.6%) to 99.375% when pulling ef3765c on Aiky30:feature/support-django-cms-4 into b866960 on nephila:develop.

[codecov]

Codecov Report

Merging #41 (ef3765c) into develop (b866960) will decrease coverage by 1.24%.
The diff coverage is 77.77%.

@@             Coverage Diff             @@
##           develop      #41      +/-   ##
===========================================
- Coverage   100.00%   98.75%   -1.25%     
===========================================
  Files            4        6       +2     
  Lines          152      161       +9     
  Branches        23       24       +1     
===========================================
+ Hits           152      159       +7     
- Misses           0        1       +1     
- Partials         0        1       +1     

Flag	Coverage Δ
unittests	98.75% <77.77%> (-1.25%)	⬇️

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Impacted Files	Coverage Δ
djangocms_redirect/admin.py	93.10% <60.00%> (-6.90%)	⬇️
djangocms_redirect/compat.py	100.00% <100.00%> (ø)
djangocms_redirect/__init__.py	100.00% <0.00%> (ø)

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