Update docs/pip_sphinxext.py

Co-authored-by: Tzu-ping Chung <uranusjr@gmail.com>

Author: luismedel

docs/pip_sphinxext.py

@@ -150,7 +150,7 @@ def _format_option(
             "",
             line,
             "",
-            "    " + opt_help,
+            f"    {opt_help}",
             "",
             f"    (environment variable: {env_var_names_src})",
             "",