Timing issue after using `set_mox_global`

I upgraded Mox from 1.1.0 to 1.2.0 and now have an intermittent problem.

I have two test files in a directory, the first of which sets Mox to global mode, and the second of which does not.

I've never had problems with these files before, but since upgrading to 1.2.0 the second file will sometimes now fail multiple tests with an error like:

     ** (ArgumentError) cannot add expectations/stubs to JitsiMeet.Token.JwtMock in the current process (#PID<0.1826.0>) because Mox is in global mode and the global process is #PID<0.1814.0>. Only the process that set Mox to global can set expectations/stubs in global mode

It's not consistent, but I would estimate it occurs on roughly 1/8 test runs. Looking at the code changes I would think this must have to do with NimbleOwnership.allow having a timeout. I didn't look farther than seeing that. I would think that the setting of the global mode should end when the test module exits, (i.e. from an on_exit function), not based on a timeout.

Erlang/OTP 26 [erts-14.2.5] [source] [64-bit] [smp:2:2] [ds:2:2:10] [async-threads:1] [jit:ns]

Elixir 1.14.5 (compiled with Erlang/OTP 26)

Reproduce the intermittent failures using the two test files described in the issue, then inspect NimbleOwnership.allow and the timeout-based handling of Mox global mode. Compare that lifecycle with the proposed on_exit behavior; done means the second test file no longer inherits global mode and the affected tests pass reliably across repeated runs.