Test `tarray_of_channels` fails on OpenBSD

[euantorano]

The parallel/tarray_of_channels test fails on OpenBSD with the following output:

Category: parallel
Name: tests/parallel/tarray_of_channels.nim C
Action: run
Result: reOutputsDiffer
-------- Expected -------
(x: 0.0)
(x: 0.0)
(x: 0.0)
test
test
test
--------- Given  --------
(x: 0.0)
(x: 0.0)
(x: 0.0)
pthread_mutex_destroy on mutex with waiters!
pthread_mutex_destroy on mutex with waiters!
pthread_mutex_destroy on mutex with waiters!
test
test
test

This is due to OpenBSD's pthread_mutex_destroy function writing this message to stderr if a mutex isn't unlocked before destroying it:

• https://github.com/openbsd/src/blob/47f3b7d8926660a01a14e2ea3408f97d45323072/lib/libc/thread/rthread_mutex.c#L81
• https://github.com/openbsd/src/blob/b66614995ab119f75167daaa7755b34001836821/lib/libc/thread/rthread_sync.c#L70

[euantorano]

@Araq This issue wants re-opening if you wouldn't mind, it accidentally got linked to the CI PR. This test is currently disabled due to the failures.