python-chess v0.30.0

Changes:

* **Dropped support for Python 3.5.**
* Remove explicit loop arguments in `chess.engine` module, following
  https://bugs.python.org/issue36373.

Bugfixes:

* `chess.engine.EngineProtocol.returncode` is no longer poisoned when
  `EngineProtocol.quit()` times out.
* `chess.engine.PlayResult.info` was not always of type
  `chess.engine.InfoDict`.

Features:

* The background thread spawned by `chess.engine.SimpleEngine` is now named
  for improved debuggability, revealing the PID of the engine process.
* `chess.engine.EventLoopPolicy` now supports `asyncio.PidfdChildWatcher`
  when running on Python 3.9+ and Linux 5.3+.
* Add `chess.Board.san_and_push()`.