Python-logstash-async

* Properly require Python >= 3.11.
The previous release had a wrong requirement set unfortunately.

* **Breaking change**: drop support for 3.8, 3.9 and 3.10.
* Catch errors on TCP/UDP socket closing to prevent requeuing of events
(98, 100).
* Add new setting to configure batch sizes for Beats transport (93).
* Support URL path in HttpTransport (103, Seyyed Mohammad Borghei).
* LogstashFormatter: Move top_level_field_set creation to __init__
to ease setting FORMATTER_LOGSTASH_MESSAGE_FIELD_LIST after
importing the formatter class (96, 97, feliixx).

* Add ECS (Elastic Common Schema) formatter support (91, Andrii Lahuta).
* On closing UDP/TCP socket, make sure it is reset (89, 92).
* Ensure to not check for socket write buffer if disabled.

* Implement get_non_flushed_event_count() for MemoryCache (88).

* Wait for empty socket write buffer only if "fnctl" is available (82).
* Wait at most 30s for empty socket write buffer (83).
* Read pending events from database on startup for immediate flushing (85).

* Add a wait until all data is sent, before closing socket on TCP
transport (81, Alisher Nazarkhanov).
* Explicitly shutdown the socket connection in Udp/TcpTransport to
prevent peer connection errors.
* Implement optional database VACUUM on shutdown (80).