Update sphinxlint/__main__.py

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>

Author: rtobar

sphinxlint/__main__.py

@@ -61,6 +61,8 @@ def __call__(self, parser, namespace, values, option_string=None):
     class StoreNumJobsAction(argparse.Action):
         def __call__(self, parser, namespace, values, option_string=None):
             setattr(namespace, self.dest, self._job_count(values))
+
+        @staticmethod
         def _job_count(values):
             if values == "auto":
                 return os.cpu_count()