Merge branch 'handle-empty-args' into 'master'

Prevent an IndexError when running manage.py without arguments

See merge request !1428

arkindex/project/settings.py

@@ -28,7 +28,7 @@ BASE_DIR = Path(_base_dir) if _base_dir else Path(__file__).resolve().parent.par
 TEST_ENV = 'test' in sys.argv
 
 # Matches ./manage.py shell[_plus] and arkindex shell[_plus] to disable Sentry reporting
-DJANGO_SHELL = sys.argv[1] in ('shell', 'shell_plus')
+DJANGO_SHELL = len(sys.argv) > 1 and sys.argv[1] in ('shell', 'shell_plus')
 
 CONFIG_PATH = Path(os.environ.get('CONFIG_PATH', BASE_DIR / 'config.yml'))
 parser = get_settings_parser(BASE_DIR)