crash when swap_manager init times out

[accumulator]

see

electrum/electrum/gui/qt/main_window.py

Lines 1208 to 1215 in 6a4b398

	def initialize_swap_manager(self, transport):
	sm = self.wallet.lnworker.swap_manager
	if not sm.is_initialized.is_set():
	async def wait_until_initialized():
	try:
	await asyncio.wait_for(sm.is_initialized.wait(), timeout=5)
	except asyncio.TimeoutError:
	return

results in

  4.63 | I | submarine_swaps.NostrTransport | starting nostr transport with pubkey: 464e1f8f51556548f7c467b8d22e7f2b457cccf20aaec3c6a0fa7211866e49be
  4.63 | I | submarine_swaps.NostrTransport | nostr relays: ['wss://nos.lol', 'wss://relay.damus.io', 'wss://brb.io', 'wss://nostr.mom']
  4.83 | I | submarine_swaps.NostrTransport | connected relays: []

...


21.30 | I | submarine_swaps.NostrTransport | shutting down nostr transport
 21.30 | I | submarine_swaps.NostrTransport | taskgroup stopped.
 21.30 | E | submarine_swaps.NostrTransport | Exception in stop: ValueError('Set of Tasks/Futures is empty.')
Traceback (most recent call last):
  File "/home/sander/projects/electrum/electrum/electrum/util.py", line 1198, in wrapper
    return await func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sander/projects/electrum/electrum/electrum/submarine_swaps.py", line 1362, in stop
    await self.relay_manager.close()
  File "/home/sander/projects/electrum/electrum/packages/electrum_aionostr/relay.py", line 215, in close
    await self.broadcast('close', self.taskgroup)
  File "/home/sander/projects/electrum/electrum/packages/electrum_aionostr/relay.py", line 201, in broadcast
    return await asyncio.wait(results, return_when=asyncio.ALL_COMPLETED)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/asyncio/tasks.py", line 454, in wait
    raise ValueError('Set of Tasks/Futures is empty.')
ValueError: Set of Tasks/Futures is empty.
 21.30 | E | gui.qt.exception_window.Exception_Hook | exception caught by crash reporter
Traceback (most recent call last):
  File "/home/sander/projects/electrum/electrum/electrum/gui/qt/channels_list.py", line 370, in <lambda>
    menu.addAction(read_QIcon('update.png'), _('Submarine swap'), lambda: self.main_window.run_swap_dialog())
                                                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sander/projects/electrum/electrum/electrum/gui/qt/main_window.py", line 1178, in run_swap_dialog
    with transport:
         ^^^^^^^^^
  File "/home/sander/projects/electrum/electrum/electrum/submarine_swaps.py", line 1327, in __exit__
    fut.result(timeout=5)
  File "/usr/lib/python3.12/concurrent/futures/_base.py", line 456, in result
    return self.__get_result()
           ^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result
    raise self._exception
  File "/home/sander/projects/electrum/electrum/electrum/util.py", line 1198, in wrapper
    return await func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sander/projects/electrum/electrum/electrum/submarine_swaps.py", line 1362, in stop
    await self.relay_manager.close()
  File "/home/sander/projects/electrum/electrum/packages/electrum_aionostr/relay.py", line 215, in close
    await self.broadcast('close', self.taskgroup)
  File "/home/sander/projects/electrum/electrum/packages/electrum_aionostr/relay.py", line 201, in broadcast
    return await asyncio.wait(results, return_when=asyncio.ALL_COMPLETED)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/asyncio/tasks.py", line 454, in wait
    raise ValueError('Set of Tasks/Futures is empty.')
ValueError: Set of Tasks/Futures is empty.