[requirements] Rely on django-configurations to manage Django settings

requirements/base.in

@@ -1,2 +1,3 @@
+django-configurations
 django>=5.1,<5.2
 pip-lock

requirements/base.txt

@@ -1,4 +1,4 @@
-# SHA1:e1677d1f2cf78dc26b96c6f8b02f0a0192f1d402
+# SHA1:78e037786a8e05baa81b92ef0373bd8fc1069bd9
 #
 # This file is autogenerated by pip-compile-multi
 # To update, run:
@@ -8,6 +8,10 @@
 asgiref==3.8.1
     # via django
 django==5.1.3
+    # via
+    #   -r requirements/base.in
+    #   django-configurations
+django-configurations==2.5.1
     # via -r requirements/base.in
 pip-lock==2.12.0
     # via -r requirements/base.in