test_sendfile_close_peer_in_the_middle_of_receiving fails on ppc64le

Bug report

Bug description:

When running the test suite for Python 3.12 on ppc64le architecture, this test fails (it passes perfectly well on other architectures):

[ 6080s] FAIL: test_sendfile_close_peer_in_the_middle_of_receiving (test.test_asyncio.test_sendfile.EPollEventLoopTests.test_sendfile_close_peer_in_the_middle_of_receiving)
[ 6080s] ----------------------------------------------------------------------
[ 6080s] Traceback (most recent call last):
[ 6080s]   File "/home/abuild/rpmbuild/BUILD/Python-3.12.5/Lib/test/test_asyncio/test_sendfile.py", line 466, in test_sendfile_close_peer_in_the_middle_of_receiving
[ 6080s]     with self.assertRaises(ConnectionError):
[ 6080s] AssertionError: ConnectionError not raised

Complete build log

CPython versions tested on:

3.12

Operating systems tested on:

Linux

从 Lib/test/test_asyncio/test_sendfile.py 开始，重点检查第 466 行的 test_sendfile_close_peer_in_the_middle_of_receiving，并以提供的 build log 作为上下文，在 Linux ppc64le 上复现该失败。比较该测试在其他架构上的行为；完成标准是该测试在 ppc64le 上能够按预期可靠地引发 ConnectionError，同时不会导致其他平台出现回归。