update the on device delegate compatibility (#4060)

Summary:
Pull Request resolved: https://github.com/pytorch/executorch/pull/4060

As discussed offline, mainly two changes in this diff
- add a unit test in the demo backend that will throw `DelegateInvalidCompatibility` when getting a wrong version
- Add doc block for the compatibility error report during init

Reviewed By: mergennachin, kirklandsign

Differential Revision: D58986515

fbshipit-source-id: 0b1da8a770fe564485ceb3a28c3d13831ee37528