Fixed #32260 -- Made View.as_view() do not use update_wrapper().

View.as_view() should not use update_wrapper() for copying attributes
it's unintended and have side-effects such as adding `self` to the
signature.

This also fixes system check for arguments of custom error handler
views with class-based views.

Co-authored-by: Nick Pope <nick.pope@flightdataservices.com>

tests/check_framework/urls/bad_class_based_error_handlers.py

@@ -0,0 +1,16 @@
+urlpatterns = []
+
+
+class HandlerView:
+    @classmethod
+    def as_view(cls):
+        def view():
+            pass
+
+        return view
+
+
+handler400 = HandlerView.as_view()
+handler403 = HandlerView.as_view()
+handler404 = HandlerView.as_view()
+handler500 = HandlerView.as_view()

tests/check_framework/urls/good_class_based_error_handlers.py

@@ -0,0 +1,9 @@
+from django.views.generic import View
+
+urlpatterns = []
+
+
+handler400 = View.as_view()
+handler403 = View.as_view()
+handler404 = View.as_view()
+handler500 = View.as_view()