ECU_State bug

[polybassa]

          Hi @polybassa, sorry for bothering. If you have the time there's a small bug

Traceback (most recent call last):
  File "/opt/hostedtoolcache/PyPy/3.9.16/x64/lib/pypy3.9/threading.py", line 980, in _bootstrap_inner
    self.run()
  File "/opt/hostedtoolcache/PyPy/3.9.16/x64/lib/pypy3.9/threading.py", line 917, in run
    self._target(*self._args, **self._kwargs)
  File "<input>", line 25, in answering_machine_thread
  File "/home/runner/work/scapy/scapy/scapy/ansmachine.py", line 210, in __call__
    self.sniff()
  File "/home/runner/work/scapy/scapy/scapy/ansmachine.py", line 216, in sniff
    sniff(**self.optsniff)
  File "/home/runner/work/scapy/scapy/scapy/sendrecv.py", line 1310, in sniff
    sniffer._run(*args, **kwargs)
  File "/home/runner/work/scapy/scapy/scapy/sendrecv.py", line 1253, in _run
    session.on_packet_received(p)
  File "/home/runner/work/scapy/scapy/scapy/sessions.py", line 109, in on_packet_received
    result = self.prn(pkt)
  File "/home/runner/work/scapy/scapy/scapy/ansmachine.py", line 172, in reply
    reply = self.make_reply(pkt)
  File "/home/runner/work/scapy/scapy/scapy/contrib/automotive/ecu.py", line 681, in make_reply
    if not resp.supports_state(self._ecu_state):
  File "/home/runner/work/scapy/scapy/scapy/contrib/automotive/ecu.py", line 544, in supports_state
    return any(s == state or state in s for s in self.__states)
  File "/home/runner/work/scapy/scapy/scapy/contrib/automotive/ecu.py", line 544, in <genexpr>
    return any(s == state or state in s for s in self.__states)
  File "/home/runner/work/scapy/scapy/scapy/contrib/automotive/ecu.py", line 119, in __contains__
    return all(s in self._expand() for s in item._expand())
  File "/home/runner/work/scapy/scapy/scapy/contrib/automotive/ecu.py", line 54, in _expand
    *[self._flatten(v) for v in self.__dict__.values()]):
  File "/home/runner/work/scapy/scapy/scapy/contrib/automotive/ecu.py", line 54, in <listcomp>
    *[self._flatten(v) for v in self.__dict__.values()]):
RuntimeError: dictionary changed size during iteration
Transition for edge (session1, session2tp1) failed
Error entering path [session1, session2tp1, security_level2session2tp1]

Originally posted by @gpotter2 in #3869 (comment)

[polybassa]

Apparently, a listcomp in EcuState._expand got changed during operations on the list.