Fix cancel states

[anbraten]

closes #2875
closes #833
closes #2062
closes #2911
closes #2197
closes #3848

Changes

• use specific states for workflow and step updates
• var renamings and comment improvements for improved readability
• remove exit-code handling from workflow as workflow have no exit-code
• wait for traces client.Update() which updates the step states before client.Done() is called so the workflows steps states are saved before we determine the workflows state from them

[6543]

@anbraten beside the lint issue it looks ready

[anbraten]

Yes, the general refactoring should be done. The runner_test could be enhanced. And it would be nice if someone reviewing would have a closer look on the switch of Exited to the Finished property, just to make sure I haven't missed anything.