deprecate CanCreateMixin

Les motifs de cette déprécation sont indiqués dans la documentation.
Le mixin a été remplacé par `PermissionRequiredMixin` dans les endroits où ce remplacement était aisé.

core/auth/mixins.py

@@ -23,6 +23,7 @@
 #
 
 import types
+import warnings
 from typing import TYPE_CHECKING, Any, LiteralString
 
 from django.contrib.auth.mixins import AccessMixin, PermissionRequiredMixin
@@ -148,6 +149,24 @@ class CanCreateMixin(View):
             to create the object of the view.
     """
 
+    def __init_subclass__(cls, **kwargs):
+        warnings.warn(
+            f"{cls.__name__} is deprecated and should be replaced "
+            "by other permission verification mecanism.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        super().__init_subclass__(**kwargs)
+
+    def __init__(self, *args, **kwargs):
+        warnings.warn(
+            f"{self.__class__.__name__} is deprecated and should be replaced "
+            "by other permission verification mecanism.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+        super().__init__(*args, **kwargs)
+
     def dispatch(self, request, *arg, **kwargs):
         res = super().dispatch(request, *arg, **kwargs)
         if not request.user.is_authenticated: