Unexpected rebase error in Neos Ui must fail CI

[mhsdesign]

Currently the CI just accepts that a discard was not possible and continues.

Discarding happens at the start of every tests (where the success should be asserted)

And this behaviour can even generate a false positive in the case of

FIX #3184: Discarded node move changes are reflected correctly in the document tree
 ✓ Scenario #2: Moved nodes do not just disappear after discarding the move change

as we try to discard - which failed in my case while debugging - and then (no surprise) the nodes of course still exist in the tree, but we didnt assert the correct position but just that they can be found somewhere.

...

For error flashmessages we handle it the way that we assert that no console errors should be logged... maybe we should do the same and just write to the console? Or assert that the dialog looks like a success.