test_crash_setuid_unpackaged fails with psutil.NoSuchProcess: process no longer exists

test_crash_setuid_unpackaged is racy and rarely fails with:

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ERROR: test_crash_setuid_unpackaged (tests.integration.test_signal_crashes.T)
report generation for unpackaged setuid program
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Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/psutil/_pslinux.py", line 1661, in wrapper
    return fun(self, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/psutil/_pslinux.py", line 1782, in cmdline
    data = f.read()
ProcessLookupError: [Errno 3] No such process

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/tmp/autopkgtest.ukiC2X/autopkgtest_tmp/tests/integration/test_signal_crashes.py", line 746, in test_crash_setuid_unpackaged
    self.do_crash(
  File "/tmp/autopkgtest.ukiC2X/autopkgtest_tmp/tests/integration/test_signal_crashes.py", line 918, in do_crash
    command_process = self.wait_for_gdb_child_process(
  File "/tmp/autopkgtest.ukiC2X/autopkgtest_tmp/tests/integration/test_signal_crashes.py", line 1088, in wait_for_gdb_child_process
    cmdline = process.cmdline()
  File "/usr/lib/python3/dist-packages/psutil/__init__.py", line 684, in cmdline
    return self._proc.cmdline()
  File "/usr/lib/python3/dist-packages/psutil/_pslinux.py", line 1665, in wrapper
    raise NoSuchProcess(self.pid, self._name)
psutil.NoSuchProcess: process no longer exists (pid=3767)

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Failing autopkgtest: https://autopkgtest.ubuntu.com/results/autopkgtest-kinetic/kinetic/arm64/a/apport/20220825_140850_23979@/log.gz