Remove an obsolete command used for testing

The test using this was removed in a045609934.

tests/management/commands/old_optparse_command.py

@@ -1,16 +0,0 @@
-from optparse import make_option
-from django.core.management.base import BaseCommand
-
-
-class Command(BaseCommand):
-
-    # Used by a specific test to see how unupgraded
-    # management commands play with configurations.
-    # See the test code for more details.
-
-    option_list = BaseCommand.option_list + (
-        make_option('--arg1', action='store_true'),
-    )
-
-    def handle(self, *args, **options):
-        pass