In python 3.11 async.run() always tries to convert repr of the result of a coroutine as integer while fetching sigint handler. This makes the test materialize the whole tensor in memory. This changes the test co-routine to return nothing to avoid triggering this bug.

In python 3.11 async.run() always tries to convert repr of the result of a coroutine as integer while fetching sigint handler. This makes the test materialize the whole tensor in memory. This changes the test co-routine to return nothing to avoid triggering this bug. #43094