[llvm] [OrcJIT] distinguish normal and abrupt TaskDispatcher shutdown (PR #154356)

[Lang Hames via llvm-commits]

https://github.com/lhames commented:

It'd be interesting to make the unit-tests parametrizable by dispatcher, but I think that we should make each variable access dependent on its respective task being complete, rather than introducing a distinct run-to-complete concept.

https://github.com/llvm/llvm-project/pull/154356