BZ1154557 Signal Start Event doesn't map event data from ksession.signalEvent() to a process variable
- Test case

(cherry picked from commit 5bca3d249d89a3db882b755961df3deff2fb9a69)
BZ1154557 Signal Start Event doesn't map event data from ksession.signalEvent() to a process variable
- Addional test improvement for testMessageStart
- Fixing bpmn files

(cherry picked from commit ad4fafa13cd62123fe8358a5c3d6e7524dde8730)