Add MIRI to CI

[notgull]

We should add MIRI tests to the CI here. It looks like some of the tests are broken under CI at the moment. See here.

cc @taiki-e When you originally set up the CI for this crate, did you intentionally avoid MIRI here for this reason?

[taiki-e]

I'm not the person who originally set up the CI for this crate...

See here.

It shows as "cancelled", is it an automatic cancellation or a manual cancellation by you?

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If you have not made any changes to the test files, it is not surprising that the test of this crate takes a long time to run, since the iterations are too many to run in Miri. In that case, you can reduce the number of iterations as I did with crossbeam and concurrent-queue tests (e.g., smol-rs/concurrent-queue@434e8e9).

If you still have problems, I have not seen similar problems with crossbeam-channel, so I'm considering the possibility that the problem is something that is not used in crossbeam-channel, such as event-listener. You may want to see if versions that use older event-listener have the same problem.