Incorrect implementation of `truncate` in `test_free_threading` for IO

[picnixz]

Bug report

Bug description:

 def truncate(barrier, b, *ignore):
 barrier.wait()
 try: b.truncate(0)
 except: BufferError # ignore exported buffer

should be

 def truncate(barrier, b, *ignore):
 barrier.wait()
 try: b.truncate(0)
 except BufferError: pass # ignore exported buffer

instead.

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-138360: Fix test_free_threading for IO objects #138359

[picnixz]

I suggested including this fix into the backport directly instead of having a new PR again for 3.14 only.