Remove django.utils baseconv and datetime_safe modules (#1977)

Author: q0w

django-stubs/utils/baseconv.pyi

@@ -247,9 +247,7 @@ django.test.client.AsyncClient.put
 django.test.client.AsyncClient.trace
 django.test.runner.DiscoverRunner.__init__
 django.test.runner.RemoteTestResult.addDuration
-django.utils.baseconv
 django.utils.choices
-django.utils.datetime_safe
 django.utils.deprecation.RemovedInDjango50Warning
 django.utils.deprecation.RemovedInDjango60Warning
 django.utils.html.VOID_ELEMENTS

django-stubs/utils/datetime_safe.pyi

@@ -394,15 +394,13 @@
         import django.utils.archive
         import django.utils.asyncio
         import django.utils.autoreload
-        import django.utils.baseconv
         import django.utils.cache
         import django.utils.connection
         import django.utils.crypto
         import django.utils.datastructures
         import django.utils.dateformat
         import django.utils.dateparse
         import django.utils.dates
-        import django.utils.datetime_safe
         import django.utils.deconstruct
         import django.utils.decorators
         import django.utils.deprecation