Deprecate SPI transaction event notifications

The SPI API for monitoring thread to transaction association changes needs deprecating. It was introduced in JBTM-2343 (Interface for tracking thread/transaction association changes) and WFLY-4923.

The ability to listen for such changes has been re implemented by WFTC (see WFLY commit 7ef53b800:- Updated EJB client integration: Fixes to start bringing Transactions, EJB, and Discovery together) so we should stop generating these events.