Fixed #23808 -- Documented that migrations table is created when using runserver…

Fixed #23808 -- Documented that migrations table is created when using runserver without migrating first.

docs/ref/django-admin.txt

@@ -958,6 +958,9 @@ If the :doc:`staticfiles</ref/contrib/staticfiles>` contrib app is enabled
 (default in new projects) the :djadmin:`runserver` command will be overridden
 with its own :ref:`runserver<staticfiles-runserver>` command.
 
+If :djadmin:`migrate` was not previousy executed, the table that stores the
+history of migrations is created at first run of ``runserver``.
+
 .. django-admin-option:: --noreload
 
 Use the ``--noreload`` option to disable the use of the auto-reloader. This