[WFLY-2065] Update jboss-transaction-spi

This PR means that the JPA subsystem will no longer need to hard code the transaction timeout reaper thread name.

The jboss-transactions-spi revision update (see https://github.com/jbosstm/jboss-transaction-spi for details) includes:

  - [JBTM-1556] new method to determine TM reaper timeout threads
  - [JBTM-1641] Don't dump exception when debug logging