Fix intermittent failure in Balking pattern describe in #699

[staillebois]

Fix intermittent failure

• Enable the "wash" test for the Balking pattern

Solves #699

• The problem here was that sometimes, the ExecutorService execute the second instruction instead of the first one.
  We can see it in the log file : https://api.travis-ci.org/v3/job/329176022/log.txt
  (the pool-1-thread-2 was launch before).
  So the machineStateGlobal variable was set to ENABLED.

• The fix proposed here is to set the machineStateGlobal variable for each execution. It will not depend anymore on the order.