Add an example on how to configure with dictConfig + StdlibFormatter

```python
LOGGING_CONFIG = {
"format": "[%(asctime)s.%(msecs)03d] %(levelname)s %(name)s:%(funcName)s: %(message)s",
"datefmt": "%d/%b/%Y:%H:%M:%S",
},
+ "ecs": {
+ "()": "ecs_logging.StdlibFormatter"
+ },
"access": {"format": "%(message)s",},
},
"handlers": {
"default": {
"class": "logging.StreamHandler",
"stream": "ext://sys.stdout",
- "formatter": "default",
+ "formatter": "ecs",
},
"access_logs": {
"class": "logging.StreamHandler",
```

The issue provides a Python LOGGING_CONFIG snippet showing dictConfig with ecs_logging.StdlibFormatter, but it does not name a documentation file or example location. Locate the project's configuration examples, add this usage there, and verify that the documented formatter and handler configuration matches the requested snippet.

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