Fixes bug 1087656
In euca exercise, the timeout for one of the volume operations was
specified as ASSOCIATE_TIMEOUT, whereas the timeout error message was
mentioning RUNNING_TIMEOUT. This fix changes the timeout to
RUNNING_TIMEOUT so that it is consistent with the error message.
As RUNNING is usually larger than ASSOCIATE, it leaves more time for the
volume operation.
Change-Id: Ic016c7920ae6e4ec9a476bb5612b7df9eed01c75