Python 3 is built frequently on the Fedora infra on AArch64 and the test_faulthandler test doesn't fail there. Recent example of build:
https://koji.fedoraproject.org/koji/buildinfo?buildID=1236594

Direct link to AArch64 build logs (build.log):
https://kojipkgs.fedoraproject.org//packages/python3/3.7.2/5.fc29/data/logs/aarch64/build.log

Extract:

0:02:37 load avg: 5.99 [177/414] test_faulthandler passed (41 sec 925 ms) -- running: test_concurrent_futures (1 min 30 sec)
...
0:03:10 load avg: 10.21 [190/414] test_faulthandler passed (1 min 2 sec) -- running: test_gdb (44 sec 52 ms), test_concurrent_futures (1 min 56 sec)

The test is run on a Python compiled in release mode then on a Python compiled in debug mode. The test pass in both cases.

I close the issue. It seems like the bug has been fixed indirectly since this bug has been reported.

Thanks for your bug report Andreas Schwab :-)