[io] set new io_uring taskrun flags on linux 5.19

Linux 5.19 introduces new flags to control how the kernel notifies tasks
running in user space about task_work to run generating completions.
Prior to 5.19 the kernel would interrupt the running tasks the new introduced
flags prevent the forceful interruption and set a flag in io_uring.
The flag signals io_uring_peek to enter the kernel to execute the available
task_work.

The man page claims that setting the flags is beneficial for most applications.
Only downside I see is that io-stealing is less effective since CQEs are
not immediately created.
52 jobs for io_uring_set_taskrun_flags in 16 minutes and 40 seconds (queued for 3 seconds)