TSAN shows a data race in the unit tests

[jcjones]

RUSTFLAGS="-Z sanitizer=thread" rustup run nightly cargo test

running 4 tests
test u2fprotocol::tests::test_init_device ... ok
test u2fprotocol::tests::test_ping_device ... ok
test u2fprotocol::tests::test_sendapdu ... ok
==================
WARNING: ThreadSanitizer: data race (pid=35046)
  Write of size 8 at 0x7e8000284070 by thread T4:
    #0 memmove <null>:65020504 (libclang_rt.tsan_osx_dynamic.dylib:x86_64+0xc206)
    #1 pthread_setname_np <null>:63970968 (libsystem_pthread.dylib:x86_64+0x421a)

  Previous write of size 8 at 0x7e8000284070 by thread T1:
    #0 memmove <null>:65020504 (libclang_rt.tsan_osx_dynamic.dylib:x86_64+0xc206)
    #1 pthread_setname_np <null>:63970968 (libsystem_pthread.dylib:x86_64+0x421a)

  Thread T4 (tid=5431922, running) created by main thread at:
    #0 pthread_create <null>:65020504 (libclang_rt.tsan_osx_dynamic.dylib:x86_64+0x7121)
    #1 std::sys::imp::thread::Thread::new::hb0ee40c469bc0ac1 thread.rs:72 (u2fhid-67c8d56994e664bc:x86_64+0x10006d575)
    #2 __rust_maybe_catch_panic lib.rs:98 (u2fhid-67c8d56994e664bc:x86_64+0x10007176c)
    #3 start <null>:63965880 (libdyld.dylib:x86_64+0x5234)

  Thread T1 (tid=5431919, finished) created by main thread at:
    #0 pthread_create <null>:65020504 (libclang_rt.tsan_osx_dynamic.dylib:x86_64+0x7121)
    #1 std::sys::imp::thread::Thread::new::hb0ee40c469bc0ac1 thread.rs:72 (u2fhid-67c8d56994e664bc:x86_64+0x10006d575)
    #2 __rust_maybe_catch_panic lib.rs:98 (u2fhid-67c8d56994e664bc:x86_64+0x10007176c)
    #3 start <null>:63965880 (libdyld.dylib:x86_64+0x5234)

SUMMARY: ThreadSanitizer: data race (libsystem_pthread.dylib:x86_64+0x421a) in pthread_setname_np
==================
test u2fprotocol::tests::test_sendrecv_multiple ... ok

test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out