Previously the controllers would proceed with additional creates,
updates, or deletes if 1 failed. That could potentially result in
scenarios where an EndpointSlice create or update failing while a delete
worked. This updates the logic so that removals will not happen if
additions fail.
The KEP specifies that the controller will "mirror all labels from the
Endpoints resource and all endpoints and ports from the corresponding subset".
I'd missed that in my initial implementation, this should fix that.
This mirrors an earlier fix to the EndpointSlice controller. I'll make a
follow up PR to move this component to a shared package, but that seems
beyond the scope of a bug fix PR.
