Python lint: Ruff rule PLW1510 -- subprocess-run-without-check

A subset of:
*  modelcontextprotocol#525

% `ruff check --select=PLW1510`
```
 1	PLW1510	[*] subprocess-run-without-check
```
https://docs.astral.sh/ruff/rules/subprocess-run-without-check

Author: cclauss

tests/client/test_config.py

@@ -44,7 +44,9 @@ def test_command_execution(mock_config_path: Path):
 
     test_args = [command] + args + ["--help"]
 
-    result = subprocess.run(test_args, capture_output=True, text=True, timeout=5)
+    result = subprocess.run(
+        test_args, capture_output=True, text=True, timeout=5, check=False
+    )
 
     assert result.returncode == 0
     assert "usage" in result.stdout.lower()